Mostly Steam for PC games. I try to buy from mom and pop shops whenever I do buy games. Amazon or Ebay for those harder to find items. Don't use Amazon as much since they've botched my order a few times. The big reason I used to like to use them was the extra $10 or $20 you'd get back via credit. I used it to buy more games usually. But they stopped doing that. Got burned a couple of times at Gamestop so I stopped using them altogether. Plus those lousy stickers that won't come off from used games are so annoying. But on a very rare occasion I like to stop in and check what they have.