Have some links:
Minnesota
Michigan
Iowa
Colorado
Washington
Montana - See the state map, not the bicycle map which is pretty crap.
Indiana

Those are just the ones I already knew of, or could find in five minutes. Some are more useful than others - the Michigan map is my favorite for showing NF campgrounds.

What I'd do is fill in the blank states for loose pages from a DeLorme Gazetteer, with my laptop map for backup.

Don't think you need to print and carry all these maps, either. Buy the delorme maps along the way and send them home when you're done. Print the online maps at libraries or copy places.