1. Expect to pay triple digits for a good video card. And have a good definition of how "good" you want it. Don't buy ANYTHING without doing some research; the numbers used are very confusing, and it helps to have a good baseline. I highly recommend against buying off the shelf at a computer store; that's how you get stuck with the modern equivalent of the GeForce4 MX440.
2. Xbox 360 controller. If you want guaranteed compatibility, you have to use it because of Microsoft's XInput push. You can probably still use regular controllers by using drivers. Honestly I never really use controllers except in "programs of a certain nature", so I wouldn't know.
3. I doubt Steam has points cards. There are probably multiple ways to process payment, but I think they're all online.
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It's F-Zero. F-ZEEEEEEEEEEEEEEEEEEEEEEEEEERO!
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