In reply to kipper12:
I used a turbo trainer last winter to build up my strength after a hip replacement, with icy roads I wasn't going outside!
Whatever you get make sure you don't just pedal out the miles, you need a structured session every time you get on the turbo/rollers. I've a Garmin GPS unit that lets you set up several training sessions on your computer and download them to the unit then you just choose one of them, it beeps at you when you need to put in effort, slow down etc. This way it's quite easy to do an hour's session. Without a structure, i.e. just sat there spinning away, I can only do about 20 minutes before I'm bored stupid.
If you don't have a bike computer that can do the above then get a playlist on your mp3 player/phone and do efforts/rests to each track - good be interesting with a random play order. Some people use the sufferfest videos but you need a TV set up for them.
Here's Eddy Mercx on his rollers