I'm in a home basement in the US so I assume 15 amps per circuit in general.

You don't really need to worry about the AC circuit's current - it's 120V coming out of the wall, so 1A there would make 10A at 12V (ish, minus a bit for conversion losses) when it comes out the other side of your power supply. You'll have to build a massive rack for it to need more than a regular household 10-15A AC circuit to plug in to! :)