I'm a computer programmer and this is the first time I've done anything like this. I made it happen, so I think anybody armed with minimal carpentry skills and these simple instructions could get as good of results!
Finally, if you're looking for similar wood ideas, check out this site. I'm not affiliated with, nor have I even done business these guys (yet). I just find the projects are quite inspiring!
UPDATE: Looks like I didn't win anything. :_(
Oh well, many thanks to everyone who voted!
Also I should add that these doors have survived the winter well, including several heavy wind storms. It appears that the design is sound and should last for quite some time. (Unlike my shed roof which, well... lets just say there's never a dull moment around here.)
Step 1: The Boring Backstory
Having heard the horror stories of the limb-rending power of garage door springs I opted to shelve my DIY nature and hire a guy to come out for this one. The dude looks it over and says, "I could probably fix that if you really want me to, but these kind of doors are such junk that the manufacturer has gone out of business". Spiffy.
I had him rip them out, but that left me with gaping holes in my house in the middle of winter. Uh oh. Now what?