You can buy meat from the supermarket/butcher, but you need to supplement it to make it balanced. This is good supplement that I use from time to time
http://felineinstincts.ca/ - its a powder with all the nutrients required to make the meat balanced.
You can also buy meat that includes bones and organs minced up together, I get mine from here
http://www.food4-cats.co.uk/ - it comes in frozen packs. Mine all love most of the varieties, although we havent tried the ostrich yet!
This site is brilliant for anything to do with raw feeding and cat health
http://www.catinfo.org/ with recipes if you want to make your own. And this site is similar
http://www.catnutrition.org/index.phpMine like chicken, beef, lamb, but their favourite is definitely turkey. As to how much to feed, really depends on the individual cat really, raw is more nutrient dense though.