There have been quite a few people over on the Touring forum who have built up that Nashbar touring frame. A search or post over there would likely pull up useful threads and suggestions. From the Nashbar website, it looks like the rear dropout spacing on your frame is 132.5mm, and Nashbar claims that you can use either 130mm or 135mm axles in the rear.

I don't have any bikes with disc brakes, and thus I am no expert on disc brakes, but I am under the impression that in order to use disc brakes you need disc tabs on the rear seat stays and disc tabs on the fork. Your frame and fork do not have disc tabs. It has posts for cantilever rim brakes, which are the standard brakes found on touring bikes. So I believe you should plan on using cantilever rim brakes. You can choose either Shimano V brake cantilever style brakes, also known as linear pull, or center pull cantilever style brakes.

If you plan to take the bike on actual loaded tours at some point in the future, and you ask on the Touring forum whether or not at 200 lb body weight, you should go for 36 spokes or 32 spokes, everyone over there will recommend going for the 36 spokes so you can be confident that your wheels will hold up on tour. Here is a decent looking, inexpensive tourer type 700c wheelset, with Deore mountain bike hubs and 36 spokes, marked down to $80.00 at Bicycle Wheel warehouse. The ad says they will take up to 700*35c tire size. Good luck!

http://www.bicyclewheelwarehouse.com...d&productId=39