Browse what is essentially Etsy for printers
So this model of using a 3d printer is fine and good, but eventually, I assume you're going to want to at least investigate designing your own things, right?
When you do, you'll have a range of options for tooling.
- Graphics tools, like blender
- Graphical CAD tools
- Kind of divided into old-school engineering heavy tools like Fusion360, or FreeCAD, (and modern incarnations like OnShape), vs things that are simpler, like TinkerCAD