There are historic plan books out there (Small Houses of the 1920s, I think, and some others like that). But even the more grand homes of that era and earlier wouldn't have plans that would work for today's family. You'd have small servants' rooms, small closets, few baths, etc. I think you might be best served by developing a "look book" for the exterior look you're wanting, and then have an architect do a plan for you.

Here's a firm local to me that would work in the aesthetic you're wanting:

http://www.krumdieck.com/profile.html

Also, take a look at the website for the Alys Beach development in the Florida panhandle. The architecture is sort of a take on Antiguan/European/Bermudan, but has that Lutyens, English Arts & Crafts look. You could contact them and find out about the architects:

http://www.alysbeach.com/

You might consider a roman domus type house--they were formed around a central court, often even two. They could even be two or more stories--if the mediterranean style works for you.