How long does it take to cook a 8 lb ham???

About 15 minutes per pound will usually do it. So about 2 hours for an 8 pound ham

First thing you do, is you read the label. A great many hams you can buy in the supermarket are already cooked and all you have to do is heat 'em up and serve 'em. It'll say on the label if yours is already cooked. If it is, an hour in the oven at 325 should be sufficient. If it is raw, give it 50 minutes per pound in the oven at 325 degrees, or until the internal temperature (buy a meat thermometer, they're cheap) reaches 160 degrees.

Approximately 15 minutes per pound in a 350 degree oven.