I think body language isn't a matter of individual poses but of movement, so you'd need a video rather than photos. Never heard of anyone doing this online, though.
Body language is complex as ordinary language. How do you expect a website to decipher your whole vocabulary, let alone be able to document it without them spending lots of time with you. The best thing you can do is read a book about it.
Body language is quite relationated with theatr, so u should enrol in a theatre course! it`s very fun sometimes. Anyway, if u try to learn it in order to flirt, maybe you should prove it by yourself. In this life u only can real learn something living it!
I found some webs where someone analizes body language, but without photos and in spanish, sorry! Bye!