Try posting in the Americas trip planing forum ( http://www.advrider.com/forums/forumdisplay.php?f=57
). That area is specifically designed for this sort of question. Try a search of that forum as well. There have been several threads dealing with planning rides to AK. Good luck.
PS: get a copy of the Milepost. This is a yearly publication that provides mile by mile description of the roads to and in AK.