I don't know why there aren't more, personally I think oral sex and 69ing are much hotter and are some of my favorite sexual fantasies!
There are lots of blowjob pics around, every photo set will have them and the anal pics, but for some reason 69 pics are alot less common.
(As far as I'm concerned it should be a stock position in every photo shoot!)
Good thing is, this is a user driven forum, so you can create your own thread or make any suggestions you want. I've been thinking about creating some kind of thread like that, (most "romantic" pics, or "sixty-nine position pics" etc), so be on the lookout in the freebies area...