>>9247386relivingthepastagain does some good add-on's to the Jabba's Palace set that came out (booths, stairwells, etc).
empiretoyworks as mentioned before. He doesn't do as many buildings as he used too and is more parts and accessories now.
also on ebay look up 'acid rain diorama'. There are a few builders that are definitely inspired by Empire Toy Works. I grabbed a few pieces and that aren't as good as his work (or as sturdy) but for $15 I am happy.
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For actual store bought stuff look up the Joytoy mech playsets and the new 'Scene in Box' stuff. Some painting will need to be done to change the aesthetics
Texture painting cheap playmobil sets (typically the pirate sets) looks good for Tattooine or desert planets
