If you're just starting your search, I think the BEST thing to do is just visit every single dealer within your area. Test drive every machine you can get your hands on. Take lots of notes - not only about the machines themselves but about the dealers as well. You'll want to make sure you're going to have repair and support available when you need it!
Personally I'm a big fan of Janome, and I also like Brother though I've only used lower-end Brother sewing machines and a embroidery-only machine that's probably somewhere in the middle.