I Need Your Advice Guys

I am here to share something with every one and will welcome your suggestions or advice, i would appreciate it alot.

I lost my father way back 1999 and when he was alive he used to buy shares as i never knew what it was untill i came to this forum and heard from some places like that. I want to know how i can go about claiming back all the share that my father bought during the 80's and i need advice how i can do that.

This are the shares he bought:
First bank
UBA
7 UP
Oando
Cultix
Adswitch
UAC
Aba textile
Golden guinea
and some others i cannot remember for now

Well my father did not have a stock broker at all because he himself was just conviced by someone(his friend) to buy the shares and i do not see any certificates yet in the file where he keeps the shares.

I can see dividends that he had alrady paid of the companies, iwant to know if i can take this to the registrars of each company to verify the accounts.