As for favorite sites, the trick is to find sites with stamina...still around. Have seen many poser sites (found a list from someone Trekkie Grrrl named), but many are 404'd.

 

Daz 3d is obvious; there find some freebies (old 'secret' catalog as well, but don't have URL. Many things for V2 and up), and used to have 1 freebie a week.

Share CG another good one; has many freebies, don't have all of them, but are trying.

 

There are sites that specialize in models (mostly Daz figures, etc) There was once upon a time a listing on 'rosity that had hundreds of sites, but madness lies in viewing them all...;)

 

Hope this help