I have a copy of the book, "The Lamont Clan: 1235-1935," by H. McKechnie, from its 1984 reprinting by Scotpress in West Virginia. Occasionally you can still find a copy of one of the originals from 1938 in a library or used book shoppe, put out by Neill & Co., Ltd. (Complete with swatches of tartan and such!) Now the book has been reprinted once again (1999), courtesy of the Clan Lamont Society of North America. If you visit their homepage at http://www.jps.net/ogdenj/lamont/lamont.htm and click on Scot Shoppe, you can find info. on how to obtain a copy of your own.
It's not real easy reading (over 600 pages, including indices)and contains so much more history than just the Campbells vs. the Lamonts. If you're not quite ready to buy the book, you might want to visit RootsWeb's Books We Own project. I believe someone will do look-ups in that book for you if you fill out the proper online form and allow a little time. ;)