Here in my city, Goodwill has a 'Computer' store annex. It is a hit and miss proposition but often you find fairly recent printers with nearly full ink reserves for 10-15$ on up, as well as new ink cartridges for ink-jets and laser printers for pennies on the dollar.
When they don't have the ink cartridge I need, I've found it much cheaper to buy one of these used printers instead of new cartridges retail. I give away the still good 'old' printer I'm replacing on Freecycle or Craigslist.
I hope this helps, Cheers