Once you get on the Alaska Highway, there are few deviations available until you reach Tok, AK. We did no planning at all and the only reservation we made was at Denali a couple weeks before we wanted to stay there. You will see the same people over and over once on the Alaska Highway because everyone is going the same way. As long as you are reasonable with your driving distances, you will not have any problems finding places to stop for the night especially if you do not mind dry camping. Heck, we even dry camped in campgrounds because the price was much less. I would suggest the Church's Alaska camping book and the Milepost. For us, the Milepost was most helpful with locating wildlife and pull offs. We used the Church's book to find campgrounds. If you have a Senior Pass, make sure you bring it because there are federal campgrounds in Alaska.