I finally made a good list of 100 Social Bookmarking Sites. I verified about 800 sites and excluded the sites which are nofollow (I excluded even those which have the "upcoming" page nofollow) and those which have PR 0 or are unranked.

I definitely believe that all these 100 links will count as backlinks.

My price for one link submitted to 100 sites is 10$ if payment sent as personal and 11$ if sent as a purchase.