I'm expecting $3k in walnut veneer drawer fronts from Scherr's in 3 weeks, so I can get back to you then :)

We recently put in Barker cabinets and are very impressed with the quality and responsiveness of the company. We ordered maple frame with a wood panel.
The picture was taken just prior to our putting up backsplash , moldings and pulls

I ordered from rawdoors.com. Got raised panel maple doors that we painted a warm grey. The quality is excellent and their website is very user-friendly. Doors came in a timely manner and were very well packed. I also got them predrilled. I would definitely use them again.

Semihandmade is another online source. Someone on here posted a beautiful walnut kitchen from them. Vsalz, I think

We are very pleased with Conastoga from the Cabinet Authority. They sell entire cabinets, just boxes, just drawers or just doors in any size.

Rick is very patient and will answer a ton of questions without losing his patience. Price was far more reasonable than Lowes/HD stock cabinets.

Here's another thats been in business for 35yrs.
http://dreeswoodproducts.com/

Thanks for the replies everyone. I have 3 places in the house that I want to add doors. I will start checking them out this weekend. Please continue to add to this thread with sources for doors and your experiences with them.