Ha, you seem to have the same build as me -- I'm 5'8" and 217 lbs at the moment. I would not recommend a touring bike with 700c wheels, especially if you plan to use it for heavy touring (say 40 or more pounds of equipment). From what I have been reading, I believe mountain-type bikes or true touring bikes with 26" wheels (at least 36 spokes) are the better bet for folks like us -- much stronger than 700c wheels.
Also, mountain bikes tend to have stronger frames (although I don't know about bikes these days since most are not cromoly steel). If not interested in buying a true cro-mo tourer, I recommend looking for a good, real steel mountain bike. That is what I use -- 1993 Jamis Diablo, 19.5", with Tange MTB tubing. Very strong bike. Back in the early 1990's, mountain bikes tended to have thicker-walled tubing (the Tange MTB tubing is butted with 1.2mm thickness as compared to .8mm or less found today). Also, back then mountain bikes had rack eyelets brazed-on to the frames -- hard to find that with today's bikes.
I recommend watching ebay and picking up a used mountain bike. Some of the old Bridgestones (MB-4 or 5), Jamis Diablo, or Trek 930 bikes would work well. Maybe also Specialized Rockhopper from that era. I've seen a number of these bikes sell for under $200 shipped, and if the frame is in good shape that is a good deal especially if some components are still usable.
I recommend only taking those with hardtails (shock-less bikes). Also, I found mountain bike frames of 19" to 19.5" from center of bottom bracket to top of seat tube to be best size for my height as a touring bike (gives about 2 inches stand-over height) because more comfortable than smaller frames.
If the last, then you must calculate with your own weight and the weight of the load. Another point besides a mountainbike for touring is that you can attach front racks easier and climb mountain roads easier thanks to its geometry. Or buy a mountainbike-like touring bike, eg koga-myata's worldtraveler or any other of koga's touring bikes.
