It's simple. Don't buy inkjets.
I wouldn’t go that far. You should just buy smart. Do not buy anything with Lexmark, Epson or Canon on it (especially Lexmark, they are evil). Check beforehand if the cartridges can be refilled.
I’ve bought an HP inkjet+scanner (F350 or something) 2 years back. I print a lot. The cartridge is an HP21 cartridge. The printer costed around $60 bucks with a colour and black cartridge (multiple uses). To refill a cartridge you simply pull the sticker back, stick a needle in the hole and inject ink. It is as fast as immunising a rat. For the black cartridges (I don’t use colour) I get about 30 refills before the quality declines. A refill costs about $1 and is good for about half a ream of paper.
I’ve shopped around for cartridges also. In brand name shops a cartridge will cost around $37. I found cartridges that sell for $20 though (imported from Singapore). This is original, brand new HP21 cartridges (probably gray imports). The moral of the story is to shop around.
Also, if you are refilling, check that the cartridge doesn’t run dry (this damages the printhead and reduces the quality). As soon as you are out of ink you should refill. Another thing is that if you use Vista, use the native Vista drivers. The normal drivers are irritating (telling you the cartridge is empty when you refilled it. This doesn’t prevent printing but it is irritating).
One of my family members picked up a printer printing with an HP21 cartridge for around $40 dollars. This included the cartridges. The only catch was that it came with a funny plug that had to be replaced (probably a grey import from a funny country). HP printers are also nice for printing double sided pages.
Many cheap laser printers have the same model as cheap inkjet printers (Gillette model: Give the shaver away and sell the blades). So their refills are extremely expensive.
\rant