The racks are a hell of a lot more important than the touring frame. Bruce Gordon racks or Tubus racks are really reliable on a trip like you're proposing. Buy a LHT or a Trek 520 and put the money into the equipment.

Gordon Racks

The Latest (cheap but very well made) Performance Pannier

I'd get Bruce to make a front rack that would mount low riders AND with a rack top so that you could put a "truck rack" type of bag on it instead of a handlebar bag. That way you could fit an LED headlight as well as the LED taillight. You shouldn't ride when you'd need these but there are always times on a ride when you're too late or you have to go get something at the store in the middle of the night. The truck rack kind of bags are easily removeable and you can carry them around much easier. Moreover they're lower than a handlebar bag so when you overload them they aren't as much of a problem.

A GOOD sleeping bag, self inflating pad and a really good tent. One of those small 3 AA battery LED flashlights so that you can read before you go to sleep and find your way to the nearest tree in the dark. Anything that's left outside of the tent WILL be torn apart by raccoons so a two person tent is better than a one person tent.

Low gearing is very important. High gearing isn't. I liked someone's suggestion of a Shimano LX Trekking triple which is 48-36-26 but I'd change the lowest with a 24. I'd also use a 9-speed 11-32 or if you're not a great climber you might want the 34 but I find that to be too slow to balance well. Though when you're really tired and it's been a long day a 34 sort of floats through your head as a good idea.

I use barend shifters because they have a friction mode and they're really cheap. Many others prefer the Brifters and that's fine too.

I definitely advise a good set of CHEAP wheels such as http://cgi.ebay.com/2004-Mavic-Cosmo...QQcmdZViewItem - these are very good touring wheels.

There's only one saddle - a Brooks B17. They're pretty comfortable to start with though you slide around forward on them if you don't tilt them up a bit. But after a couple of hundred miles after they start to break in you'll LOVE it.

Bike computers are a pain in the butt because they're broken as much as they're working. But Sigma Sport makes the most reliable I've used. And I've used pretty much all of them. Cheaper is usually better.

You'll be carrying cooking gear and food as well I expect. Hiking cooking stoves and pots/pans are good. "Camping" food IS NOT. Buy your dailey food along the way for each day with a little emergency reserve. Canned beans and the like taste good as well as powering you up for the next day.

Be sure to carry an emergency roll of toilet paper with you. And carry a medical kit with Aleve for toothaches (takes a long time to start working but works better for toothaches than valium) and general aches and pains. Some LARGE bandade brand bandages - they have some 3" jobs that are handy. Some Neosporin or one of the copies. And some of those cleaning cloths that come in sealed packets so that you can clean your road rash. BRING IMODIUM and watch what you eat. You don't want to risk being on the road with diarrhea and you can take that for fact.

If you want to carry a small beltpack pepper spray to discourage varmints that's fine but you'll find putting everything in the tent at night works a lot better. Remember that raccoons can smell chocolate inside of sealed pouches and they will tear anything apart to get at them EXCEPT get too near a human. And raccoons know how to open zippers in case you weren't aware. When you leave your camp always leave the zippers at the top of their motion.