Another vote for Donek. Sean is great to deal with. And they build some of the best boards I've ever ridden - super durable too. If you have an idea of the specs you are looking for (width, length, sidecut, shape, flex), give him a call and talk with him. He may have a stock board that's a perfect fit and then you can just do a custom topsheet for it (this is an easy thing to do with Donek). If you order your board direct from Donek, it will even have your name printed on it, just behind the bindings. If you come up with a custom design, you even get to name it and he'll print that in the little box with your name, its specs and when it was made. If you look at the list of the custom race boards you'll see what I mean. Most are just named for the people he built them for, but you may notice one called "Das Amputator" that was built for a guy named Shred Gruumer.
Check out their Specs Page
for a nearly complete list of stock boards, as well as the many custom boards he's built (most of the custom ones are race boards, but he's done some custom Inclines before).
As SirMack says, Coiler does everything custom, but he's expensive and has a really long waiting list - plus he almost exclusively does carving/alpine boards.
Neversummer may do custom stuff, but I haven't dealt with them.
Prior will do some custom work for you, but not as much as Donek.
Get your order in soon. They need to get going on it if you're going to ride it when the snow flies.