Thanks. I usually use a switching wall wart, too. I'm quite familiar with household wiring, so it shouldn't be a problem. The project I have in mind is kinda like:
Only the whole Arduino circuitry and everything will be in a small enclosure about the same size, (along with a Bluetooth chip so I can control it from my phone)
Which brings me to another question about relays, but maybe I should post it in a new thread.