This proved a useful resource on Reddit, so I am moving it to it's new home on here:

For characters (and sometimes some vehicles and terrain):

• Anvil Rage Studios (previously Seb Miniatures)

• Ataraxy Emporium

• Black Remnant

• Blue Wolf Miniatures

• Dark Fire Designs

• Hokusa 3D Designs

• legionwars, has a few miniatures as well as bases

• Nyverdale Tabletop, not many but all free and that Stormparty Core...

• Order 66 Designs, have a free Darth Vader on the toilet

• Pocket Dimension Studios, also run the Only Crates Patreon

• Ravenx

• Rebel Forge, good for Geonosis

• Scythe Designs, First Order and CIS minis especially

• SkullForge Studios

• Squamous Miniatures

• Studio DR

• Thingiverse (all free), especially McAnulty Miniatures

• War Bear Studios (previously Madox 3D Design)

For terrain:

• brander roullett, has a range of stuff but the specifically SWL terrain includes Geonosis and Modular Desert Towers

• Corvus Games

• Imperial Terrain

• Printable Scenery, their Star Wars tag seems to have gone very Hobbity recently but if you dig you find some relevant bits (starting on page 7 and 8, and on 10 and 11)

• Saucermen Studios, generic sci-fi terrain but their desert set is very Tatooine

• War Scenery, also has some figures if you dig around

• ZZ Armory

Miscellaneous:

• Deadly Print Studios, have a set of effects (muzzle flash, smoke, etc) for SWL