I second the Mike and Terri Church's Alaska book and you can order it directly from them if you like at
Church's website Since they are always on the road, it might actually be quicker to order from some place that has it in stock. They list places on their site where you can purchase their books. We have several that we have used. We find the information arranged well and they give you a heads up on places to see and things to do in the area you may not have been aware of. I actually read the entire book before we left and highlighted things of interest to us, then put tabs on the pages with notes which made it easy to flip through and find the info I needed.
The Milepost was also helpful. One of us would actually read passages aloud as we drove through. There is plenty of scenery, but soooo much history and this also helped get us through some of the very long drives of wilderness.
Campgrounds are expensive. If we go back, we will plan to spend every few days in provincial parks in Canada and similar parks in Alaska. They are much cheaper, few amenities, but would cut the overall cost of your trip by a considerable amount.
Dale