I ship all my stuff out to Georgia (I'm in NY) to Langcourt Cylinder Technologies. Half the time cheaper than local and they do stellar work...they even work on F1 cars.
Don't let location decide the quality of the work. Boring is far more important than people think. I've never had a local shop do a decent job of "race" quality.
As for the guides...someone body needs to know what they are doing, an auto machine shop will screw them up most of the time because their experience with aluminum heads and small guides is very limited.
Heck, you can do the guides yourself...I do.