There is always this question: why is it that Muslims don't condemn terrorism? Of course we do, but do people listen?

Here are quotes from famous well-known Muslims denouncing terrorism.

Islamic Statements Against Terrorism
Mustafa Mashhur, General Guide, Muslim Brotherhood, Egypt; Qazi Hussain Ahmed, Ameer, Jamaat-e-Islami Pakistan, Pakistan; Muti Rahman Nizami, Ameer, Jamaat-e-Islami Bangladesh, Bangladesh; Shaykh Ahmad Yassin, Founder, Islamic Resistance Movement (Hamas), Palestine; Rashid Ghannoushi, President, Nahda Renaissance Movement, Tunisia; Fazil Nour, President, PAS – Parti Islam SeMalaysia, Malaysia; and 40 other Muslim scholars and politicians:
“The undersigned, leaders of Islamic movements, are horrified by the events of Tuesday 11 September 2001 in the United States which resulted in massive killing, destruction and attack on innocent lives. We express our deepest sympathies and sorrow. We condemn, in the strongest terms, the incidents, which are against all human and Islamic norms. This is grounded in the Noble Laws of Islam which forbid all forms of attacks on innocents. God Almighty says in the Holy Qur’an: ‘No bearer of burdens can bear the burden of another’ (Surah al-Isra 17:15).”
MSANews, September 14, 2001, http://web.archive.org/web/20010920150230/http://msanews.mynet.net/MSANEWS/200109/20010917.15.html;
Arabic original in al-Quds al-Arabi (London), September 14, 2001, p. 2, http://81.144.208.20:9090/pdf/2001/09Sep/14%20Sep%20Fri/Quds02.pdf

Shaykh Yusuf Qaradawi, Qatar; Tariq Bishri, Egypt; Muhammad S. Awwa, Egypt; Fahmi Huwaydi, Egypt; Haytham Khayyat, Syria; Shaykh Taha Jabir al-Alwani, U.S.:
“All Muslims ought to be united against all those who terrorize the innocents, and those who permit the killing of non-combatants without a justifiable reason. Islam has declared the spilling of blood and the destruction of property as absolute prohibitions until the Day of Judgment. … [It is] necessary to apprehend the true perpetrators of these crimes, as well as those who aid and abet them through incitement, financing or other support. They must be brought to justice in an impartial court of law and [punished] appropriately. … [It is] a duty of Muslims to participate in this effort with all possible means.”
Statement of September 27, 2001. The Washington Post, October 11, 2001, http://www.washingtonpost.com/wp-dyn/articles/A40545-2001Oct10.html

Shaykh Muhammed Sayyid al-Tantawi, imam of al-Azhar mosque in Cairo, Egypt:
“Attacking innocent people is not courageous, it is stupid and will be punished on the day of judgement. … It’s not courageous to attack innocent children, women and civilians. It is courageous to protect freedom, it is courageous to defend oneself and not to attack.”
Agence France Presse, September 14, 2001

Abdel-Mo’tei Bayyoumi, al-Azhar Islamic Research Academy, Cairo, Egypt:
“There is no terrorism or a threat to civilians in jihad [religious struggle].”
Al-Ahram Weekly Online, 20 – 26 September 2001, http://www.ahram.org.eg/weekly/2001/552/p4fall3.htm

Muslim Brotherhood, an opposition Islamist group in Egypt, said it was “horrified” by the attack and expressed “condolences and sadness”:
“[We] strongly condemn such activities that are against all humanist and Islamic morals. … [We] condemn and oppose all aggression on human life, freedom and dignity anywhere in the world.”
Al-Ahram Weekly Online, 13 – 19 September 2001, http://web.archive.org/web/20010915023839/http://www.ahram.org.eg/weekly/2001/551/fo2.htm

More:

Shaykh Muhammad Hussein Fadlallah, spiritual guide of the Hizbullah movement in Lebanon, said he was “horrified” by these “barbaric … crimes”:
“Beside the fact that they are forbidden by Islam, these acts do not serve those who carried them out but their victims, who will reap the sympathy of the whole world. … Islamists who live according to the human values of Islam could not commit such crimes.”
Agence France Presse, September 14, 2001

‘Abdulaziz bin ‘Abdallah Al-Ashaykh, chief mufti of Saudi Arabia:
“Firstly: the recent developments in the United States including hijacking planes, terrorizing innocent people and shedding blood, constitute a form of injustice that cannot be tolerated by Islam, which views them as gross crimes and sinful acts. Secondly: any Muslim who is aware of the teachings of his religion and who adheres to the directives of the Holy Qur’an and the sunnah (the teachings of the Prophet Muhammad) will never involve himself in such acts, because they will invoke the anger of God Almighty and lead to harm and corruption on earth.”
Statement of September 15, 2001, http://web.archive.org/web/20011009024647/http://www.saudiembassy.net/press_release/01-spa/09-15-Islam.htm

‘Abdulaziz bin ‘Abdallah Al-Ashaykh, chief mufti of Saudi Arabia:
“You must know Islam’s firm position against all these terrible crimes. The world must know that Islam is a religion of peace and mercy and goodness; it is a religion of justice and guidance…Islam has forbidden violence in all its forms. It forbids the hijacking airplanes, ships and other means of transport, and it forbids all acts that undermine the security of the innocent.”
Hajj sermon of February 2, 2004, in “Public Statements by Senior Saudi Officials Condemning Extremism and Promoting Moderation,” May 2004, http://web.archive.org/web/20040726235629/http://www.saudiembassy.net/ReportLink/Report_Extremism_May04.pdf, page 10

Shaikh Saleh Al-Luheidan, Chairman of the Supreme Judicial Council, Saudi Arabia:
“As a human community we must be vigilant and careful to oppose these pernicious and shameless evils, which are not justified by any sane logic, nor by the religion of Islam.”
Statement of September 14, 2001, in “Public Statements by Senior Saudi Officials Condemning Extremism and Promoting Moderation,” May 2004, http://web.archive.org/web/20040726235629/http://www.saudiembassy.net/ReportLink/Report_Extremism_May04.pdf, page 6

Shaikh Saleh Al-Luheidan, Chairman of the Supreme Judicial Council, Saudi Arabia:
“And I repeat once again: that this act that the United states was afflicted with, with this vulgarity and barbarism, and which is even more barbaric than terrorist acts, I say that these acts are from the depths of depravity and the worst of evils.”
Televised statement of September 2001, in Muhammad ibn Hussin Al-Qahtani, editor, The Position of Saudi Muslim Scholars Regarding Terrorism in the Name of Islam (Saudi Arabia, 2004), pages 27-28.

Shaykh Muhammad bin ‘Abdallah al-Sabil, member of the Council of Senior Religious Scholars, Saudi Arabia:
“Any attack on innocent people is unlawful and contrary to shari’a (Islamic law). … Muslims must safeguard the lives, honor and property of Christians and Jews. Attacking them contradicts shari’a.”
Agence France Presse, December 4, 2001

Council of Saudi ‘Ulama, fatwa of February 2003:
“What is happening in some countries from the shedding of the innocent blood and the bombing of buildings and ships and the destruction of public and private installations is a criminal act against Islam. … Those who carry out such acts have the deviant beliefs and misleading ideologies and are responsible for the crime. Islam and Muslims should not be held responsible for such actions.”
The Dawn newspaper, Karachi, Pakistan, February 8, 2003, http://web.archive.org/web/20030226073546/http://www.dawn.com/2003/02/08/top17.htm;
also in “Public Statements by Senior Saudi Officials Condemning Extremism and Promoting Moderation,” May 2004, http://web.archive.org/web/20040726235629/http://www.saudiembassy.net/ReportLink/Report_Extremism_May04.pdf, page 10

Shaykh Yusuf al-Qaradawi, chairman of the Sunna and Sira Council, Qatar:
“Our hearts bleed for the attacks that has targeted the World Trade Center [WTC], as well as other institutions in the United States despite our strong oppositions to the American biased policy towards Israel on the military, political and economic fronts. Islam, the religion of tolerance, holds the human soul in high esteem, and considers the attack against innocent human beings a grave sin, this is backed by the Qur’anic verse which reads: ‘Who so ever kills a human being [as punishment] for [crimes] other than manslaughter or [sowing] corruption in the earth, it shall be as if he has killed all mankind, and who so ever saves the life of one, it shall be as if he had saved the life of all mankind’ (Al-Ma’idah:32).”
Statement of September 13, 2001. English source: http://www.islamonline.net/English/News/2001-09/13/article25.shtml (link broken). Arabic original at http://www.qaradawi.net/site/topics/article.asp?cu_no=2&item_no=1665&version=1&template_id=130&parent_id=17

You can find more here- http://kurzman.unc.edu/islamic-statements-against-terrorism/