I wouldn't want 105 or Ultegra 10-speed for touring. I'd stick with 9-speed so I could use mountain bike cassettes. The 10-speed cogs and chainrings are a little thinner, and perhaps they aren't as durable.

I'd get Deore, LX, XT, or XTR hubs and derailleurs, an XT 12-34 Cassette, a Sugino crankset with 26/36/46 chainrings, and Shimano 9-speed bar end shifters. If you want to go with STI, then you should use a 9-speed road front derailleur instead; still get a mountain rear derailleur, but make sure to get one without the "rapid rise" if you don't want the STI to shift backwards. A road 9-speed crank is okay if you are strong, young, and light and it should work better with a road front derailleur.