Does anybody know of a company that prints custom, 12 month calendars? I need a fairly high-quality one, and they are proving... tricky to find!

Sharedink Pro (for pro's only) prints pretty nice ones. That's what I use for my boudoir calendars.

Millers has several styles thru Millers Press; see:

http://www.millerslab.com/info/products/press/calendars.aspx

but then post your most fabulous holiday cards on other thread, ok?
cause we're all pretty certain you, girl, set the gold standard . . .