Thingiverse – Probably the most popular site. Find anything under the sun. Most models are free, but the site can be a little wonky at times.
Thangs – Contains a fair amount of models, but the real draw is that their search function will search a bunch of other websites as well. I like to use this site when I’m looking for a specific part or item.
Cults3d – Tons of brilliant models made by talented individuals.
MyMiniFactory – A great site specializing in table top and miniatures.
Printables – Similar to thingiverse, just a whole mess of 3d models. Owned by Prusa.
