Ron Ruff at White Mountain Wheels is excellent. Zen Cyclery is another.
And you can always call FairWheel Bikes in Ariz. Troy Watson is building wheels there now. Troy is a controversial subject on many cycling forums, but he built great wheels for me and several others. Most of the complaints about him deal with his business/management/communication skills - not wheelbuilding - and my understanding is that FairWheel - a top notch shop - is doing a better job of managing the wheel building business.