I prefer using the ground meat method with an extruder type device--looks like a caulk gun. I can find 4% fat ground beef at Trader Joes for $4/lb. I do 3 lbs at a time which just fits in my Nesco dehydrator and have over a pound when finished which lasts me about a week.

As for spices I've found that you need about 1 tablespoon per pound of spices, other than salt. Its hard to get it mixed just right though, some pieces get more spices than others. About 3/4 of a teaspoon of salt per pound is all I need. I've never used sodium nitrite becuase I usually eat it within week and keep it refrigerated. Premade spice blends like Indian Garam Masala work fine.