I am launching a new website/business later this month.

It is a site where I would sell my WordPress plugins and other software, and I have yet to get the marketing plan nailed down.

I am budgeting $1000 - $1500 monthly for the marketing and am not really sure about it (is it too little? is it too much?)

Would like to know what folks with similar sites spend on marketing though so I can plan properly.

And what marketing channels should I focus on initially (facebook?, youtube? sponsored posts?)