I decided to post in this area because I thought that it was more relevant to addons than paid services (especially because it's free )
FS Trader (http://fstrader.servebbs.net) is a forum-type site that specializes in sharing addons. Although the name says "Trader", you don't have to trade, but just share, request, etc. The site is newly made, so there isn't much there, but if people start using it, that'll change instantly. Also, there may be some changes to the site itself over the next couple of weeks due to theme changes and anticipated software upgrades. Come check us out!
P.S. As soon as I have a "small community" userbase I'll probably be looking into a full domain, so don't worry about that!