Don't you hate trying to find replacement ink cartridges for your printer? I know I do, and I've had some that were almost impossible to find locally. That's what happens when you have only two stores that carry that type of thing in the town you live in. That's what the internet is for! Seriously, Carrot Ink has a huge selection and really good prices, too. For instance, you can get an HP 56 black cartridge through them for only $15.95.
They have just about every available HP printer cartridge out there & they all have a pretty price on them. They even offer a prepaid mailer that you can put your old cartridge in, send it in and they'll remanufacture it & send it back to you. They sell ink for all of the other brands to, so check them out, I think you'll be pleasantly surprised.