Halfspeed, good advice!!!

Lorrer, lets reel it in and clear up some things.

Maybe the most important thing for loaded touring is gearing!!! No strictly road setups!! no 10 speed setups!!

For loaded touring you need a triple up front, and a mountain rear cassette. (unless youre very very strong) Now the triple up front should not be a typical road triple with a 30 tooth small sprocket. Youll want something more like a 26, or maybe a 24 tooth cog. Nashbar sells a 28,38,48 (trekking crankset) that you can fit a 26 or 24 to. This is a solid crank if you cant find something in a LBS. The rear cassette, needs to have a few bigger sprockets than a typical road unit. Mountain cassettes have either a 32 or 34 tooth big sprocket. (aka granny-gear, low gear) Youll want a mountain cassette. Go with the 34 tooth, youll be very happy to have it when you need it.

Now when selecting a gearing setup like this, derailleurs have to be picked that can span such a large range. This means a mountain rear derailleur; the front has to be picked based on the size of your biggest front cog. I have the forementioned 28,38,48 front triple and had to go with a 105 road triple up front. (the MTB der I bough wouldnt work..) Now we're not talking whats better or best, were talking what works! Setups like this are not typical, so there isnt a package you can buy and bolt on, you have to pick all the parts and make them work. This is where your shop or builder (hopefully) comes in. Now honestly, from what I've read and others seem to think the same, your shop either might not have the best idea of what you're about to undertake and how to get you setup properly, or they want to make $$$ on this.

Advise from halfspeed about talking to the right people is a great idea. This board is a good first stop.

For 2.5G's you can go full custom, with racks, from a builder who knows touring. Find one within a few hours drive, visit them and get it done right. A LBS is good for some things, but for a bike that youre going to be on for months at a time, go to a true pro.

Always ask questions here. . like you said its a great resource.
and enjoy learning all this stuff along the way!!

~Steve
sorry if this seemed long and preachy, I was in a similar situation as you a few yers ago and wish I had known then what I do now!! And the bike is the tip of the iceberg!! dont even get us started on gear for your journey: )