In addition to Thompson's book, and Fiddes' E-book, that have already been mentioned, here are a couple of other resources.

My own "Patented Advice for First Time Kilt Wearers>'
http://albanach.org/advice.htm

ANd "Wearing Highland Attire" by Thomas GOrdon Mungall III
http://www.angelfire.com/biz2/tommun...andAttire.html