Hi smrachek and tomdett:
You might want to get in touch with the bicycle coordinators for the states in which you will be traveling through and need routing. Most have resources of some sort as well as printed materials. The coordinators
have a wealth of information that they can distribute for no charge. Most every state publishes a bicycle map of their state that they will send out for free. And while the maps aren't as detailed as ours, they generally offer suggested roads for cycling through their state. Here is a link to the contact information for all of the bicycle coordinators: http://www.walkinginfo.org/assistance/contacts.cfm
When you get back, I'm sure others would love to hear what routing you came up with and how it went for you.
Hope this helps with your planning.