Welcome to the Home Automation forum. Sorry that nobody has come back to you - for some reason (must be the nice weather) its been a bit quiet on here for the past week or so.
I suspect one of the reasons nobody else has posted a reply, is becuase your question is just 'too big'. It needs to be more specific. However, as a starter for 10....
I went down the X10 route as well becuase, like you, I didnt want re-wire. Once you get past the X10 niggles (the biggest being noise on the wires), then it works well, is relativly cheap, easy to install etc.
As for your other questions, well I suggest you start by looking at the x10 kit that i available, and working out from there what you want to do. The two biggest suppliers that most people use are:
UK Home Automation..... http://www.uk-automation.co.uk/home-...-c-140_82.html
and
Lets Automate... http://www.letsautomate.com/index.cf...0&URLCaller=HA
The other source of course is the postings in this fine baord. Use the search feature at the top to find posts about an aspect you are interested in, otherwise, if you have any specific questions, feel free to start a new discussion.
Like setting up home automation project, you just need to chunk it into bite size bits so that the discussion can be around a specific topic.
But welcome, and good luck.