Yes, of-course there is.
Your question is a bit vague, particularly you don't advise which printer. You can get generic ink/cartriges/refills for most printers, and they work fine. Some of the cheaper printers (Like the Samsung Color Laser I have) have DRM to limit the use of consumables but you can purchase unlocking firmware on eBay which I know for a fact works. [ In my case I get the toner in bottles and poor it into the cartridge - which has a hole which needs to be closed off with a stopper or duct tape.
You can also buy aftermarket ink/toner from eBay or elsewhere online. You do need to be a bit careful though, because the ink does need to be suitable for your printer, not all printers use identical inks.
Of-course, some brands (I like Brother Printers, but I'm sure they are not the only one) make life very easy, and you just remove a cap and poor in the toner, no hacks required.
You also get "Ink Systems" for Inkjet Printers which allow you to get bottles of aftermarket ink and feed this into an inkjet printer (Again, I think most brands are supported but Lexmark and HP are the main ones). I believe this is good if you are doing volume printing, but is not always a simple, pleasant experience.