If they aren't on the same phase, that's OK. You will just need to install this $30 plug-in device to fix that - [Link: automatedoutlet.com]

While you are just starting out you also should make some decisions on which control software you want to manage your system. HAI is a very x10 friendly system but you will probably want something else to manage the overall picture. I would recommend either HomeSeer or HAL depending on what your overall plan is. Both can be found here - [Link: automatedoutlet.com]