There are very few things to avoid. Soft unpastuerized cheeses (like Feta), sushi (or anything raw).
I recommend a website called babyfit.com – its all about being healthy while pregnant. They have areas for excersize, nutrition, your due date month (which is very helpful to have people to ask questions to). It was such a big help while I was pregnant. Now, the group of us that went through pregnancy together are still around talking about raising our kids. Lots of good stuff!! Especially because we are sleep training my son now and its so hard!!