If I was going to spend decent money on fruit trees, I'd make darn sure to get ONLY disease resistant varieties. I'd also look for a reputable source for the trees.
Adam's County Nursery in S Central Pa is one of the more reputable nurseries in the country and is in our backyard so the fruit trees are suited to our weather.
http://www.acnursery.com/acn_resistant.php
Huge price break if you order 100+. I just shared an order with my brother, FIL and neighbor to reach 100+ trees to get the break.
Only problem is they're usually sold out by this time of year.
Check QDMA.com forums to see other reputable nurseries but try to buy from your region.
Another thing I would consider is getting crabapple instead. No maintenance and they usually produce annually. Extremely hardy and deer go crazy over them.
Check out this fellas crabapples he planted from seedlings in Michigan 7 years ago.
http://www.michiganbear.com/forum/showthread.php?t=302198