Home FDM 3d printers are much more affordable than the professional grade ones that can easily reach over $20,000. The quality isn't -as- good as the professional grade ones, but it's getting there.
They typically use two types of plastic filament, ABS (think Lego plastic) and PLA (corn-based plastic), both of which are available in spools of multiple colors. There's multiple places to get spools of these plastics on the internet.
Also, Thingiverse. People make things and upload them here for you to make as well. Site is run by Makerbot so the files will all work with their models of printers but they can typically be used with other models as well.
Check this out for a few models to look at. There's many more models of home 3d printers too. :)
If you're looking into getting into 3d printing, be prepared to drop anywhere from maybe $500-$2000 or so for your first printer, some of which will come pre-assembled and ready to go, for a price. There's a pretty big price range for these printers, it totally depends on which one you want.
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