If you've not come across it already, I wanted to highlight Fit Pregnancy, a US magazine with loads of sensible online resources and exercise advice. It is a bit American, but surprisingly pragmatic for UK tastes given our differing attitudes to risk. I "liked" it on facebook and have appreciated the tips and articles (I've ignored the shopping advice).
At 35 weeks, I've been doing my best to keep as active as I can all the way through and I'm sure this has helped minimise nasty pg symptoms so far (touch wood). I just bought a fit/birthing ball so I'm going to try their recommended workout this afternoon.
www.fitpregnancy.com/