Thought I'd pass on this locale just in case anyone was interested in attempting their own Amazonian GTS collages and needed a source for backgrounds - a most excellent one, I might add.

http://www.webshots.com/

The Community area (free) also includes a search engine to help narrow down the subject that you might be looking for as prospective backdrops for your towers of femuscular power.

=====

Forgot to mention that there are (or at least the last time I looked several months ago) a number of FBBr / Fitness gallery pages in the Community section - you'll have to use the search engine to try them down, tho.