Might you happen to have a DSL reseller in the area? 'Dry loop' or 'dark DSL'.
They might be able to tell you one way or another(don't sign anything before full confirmation, such as modem blinking happily away). Even though it is still AT&T that provisions the DSL connection. Unless you are in one of those places where DSL went around you.
You could also inquire as a potential business line customer(phone business number). A 'potential' home office, since you do not yet have a business number. Gets you past the screen reading drones. Note that your phone number and address may show on their screens as already having asked for DSL.
Also if you see an AT&T truck/tech in the area. Ask him/her. They know more than phone support on where the lines are. Or a slight wire direction change may allow you to be within the 15,000 foot limit.
Removal of a 'bridge tap', may bring results.
http://en.wikipedia.org/wiki/Bridge_tap