The thing is, horse breeds have kinda spread. My mom raised Arabians in southern Indiana (US heartland) and there's a Lippezaner farm just up north from me. Medieval Times maintains an Andelusian ranch in Texas, etc. Horses are generally comfortable anywhere they have plenty of space to run and grass to graze on.
That said, in general I'd associate breeds like the Paint, Mustang, and Appaloosa with areas like Chestnut Ridge and Oasis Springs; Lippezaners and Fresians with Windenberg; Andelusians with Tartosa; Shire, Welsh Cob, etc. with Henford on Bagley; and Thouroughbreds and Quarterhorses with more or less anywhere. But I'm sure that someone who knows horses better than I do can be more specific.
