Hi,
I think you have a great looking site. If it were me, I would bring out a camera (video and stills) to installations and take pictures that self installers could reference or become more comfortable with. I would post the videos on youtube and instructables.com. The landing pages would have email links to ask questions about installation or get quotes on the whole set up. I have worked with a bunch of different shipping companies and a few will ship to residences. If I remember right, check out Adcom worldwide. They have points all over the country. The problem is that you can't really put something 8' long on a liftgate which may be required for the weight of the shipment. The only answer I can think of is to have the carrier call before delivery and schedule a time when the home owner can have a few helpers to either pull the shipment off or break it down quickly.

The phrase "how to install a garage door" is very poorly targeted in the search engines. With very little work, you could see some more traffic from this phrase. They would also bring very targeted customers.

I would also check out something like a local "habitat for humanity" http://www.brevardhabitat.com/
and see about how you could be a part of it. Maybe you could offer them garage doors for no profit. If you were to offer the installation, it could put you in contact with a lot of other subcontractors to network with, or contractors to use your doors.

I hope all goes well!