Welcome to the Club WaltOH. Be sure to scope out the frozen planet scenics in Hydra's store. There are good space pulp figures at wargames supply dump, (WSD) too.
http://www.wargamessupplydump.co.uk/ For terrain, check out armorcast
http://www.armorcast.com/ not a whole lot there but then there wasn't anything at all a little while ago. The original Flash Gordon serial was shot on old Frankenstein and Mummy sets at universal so feel free to scarf up some of those goodies. Hirst Arts
http://www.hirstarts.com/ makes silicone rubber molds for casting stuff out of dental plaster. There is a scene where Flash Gordon topples a statue of the great god Tao on top of Mings marriage party and rescues Dale Arden. Its in the comic strip and the first serial, Bruce Hirst makes a mold in his Egyptian series which works quite well for that. But all the basic Hirst molds his schematic and even his Sci Fi (There is no Sci Fi like pulp Sci Fi the standard SF stuff can ruin the ambiance.)
The cantina full of aliens is a Star Wars thingie. Hydra, GAFDOZ, and WSD have single aliens and outfits like Reaper make the odd alien figure, so keep your eyes open.
Spacemans luck, Rocketranger 0990