Tim's summary for a single cartridge is quite accurate but does not tell the whole story. The shipping on a single cartridge from PC Superstore is $8.00 but only increases to $8.52 for 8 tanks making the total cost for a single cartridge just over $ 45.00 which is still the lowest I've found when purchasing multiple tanks.
Brogala is right. When I was creating the quick summary, it was somewhat time consuming to add multiple cartridges for each of the stores and then figure out shipping for various quantities, but it looks like antonline has the lowest price for someone buying about 5 cartridges, as the total comes to 224.86 or a bit under $45/per, slightly lower than PCSuperstore.
However, I normally only buy one or two at a time as I run low. Also, shipping time can be important. Atlex ships from multiple locations and I can normally get my shipment in 1 to 2 days @ ground shipping rates, so if timeliness is important, that an extra dollar or two might be worthwhile. So, your "local" seller might be a bit higher, but can get you the ink quicker.
