One thought is to see if you can schedule your vacation to coincide with one of the workshops that Bruce Barnbaum offers - his studio/darkroom is outside of Seattle, and he knows a lot of very interesting places in the area.

As far as the food questions go - in any of the big cities, you will have no problem finding good food that meets your needs. Depending upon how strict you follow the rules, many people just say that they are vegetarians, which is accepted well most everywhere, and this allows you to be accomodated anywhere.