I'm trying to remember what we did in the classes (it was 4 years ago). It was 2 full days I think, on a weekend, and it started off with lots of info on the stages of labour, which I found more informative than the hospital classes as we had more time to discuss it.
Then we learnt various relaxation techniques that our birthing partner could do on us, and then we learnt about affirmations (and got a CD of affirmations to listen to).
It really just demystified birth for us and I walked away feeling confident and not scared of birth anymore.
It's expensive though, so I'm sure reading and listening to CDs would help a lot too if you can't do the course.