We ordered some online.
I use reconditioned cartridges regularly. I *have* had occasional problem with one not working, but generally speaking, I have good luck with them. Even if an occasional one is bad, I still save more money using them.
I generally get mine on eBay for just a few dollars each. Pay attention to the seller's feedback rating and whether the seller guarantees their cartridges to work.
My guess is that the store brand reconditioned cartridges have better quality control than the eBay ones, but they're more expensive than the ones I get on eBay.
I used to try refilling my own cartridges. It was messier, and I was getting inconsistent results (sometimes the printer heads were too dried out or something like that), so I just get the cheap reconditioned ones now.