Google Maps will route you just about anywhere, avoiding any interstate highways. Go to Google Maps, click "Get Directions", put in your starting point and destination, click "Show Options" (just below where you type your destination), check the "Avoid Highways" box and then click "Get Directions". If you can get there without taking an Interstate Highway, our overlords in Mountain View will lead the way!
For example, here is how to get from Chandler, AZ to Key West, FL without taking an Interstate. http://goo.gl/maps/T0Hry
This is how we made it from Portland, OR to Sneads Ferry, NC, to Kinsman, OH, and finally to Toronto all without taking any interstate highways. It's really easy. It just usually adds a few miles.
Bike routes may or may not work. When we looked at a few, they involved things like going the wrong way down one-way streets and riding on dedicated bike paths. Obviously a no-go on our Symbas.
Routing is easy, so get out there and ride!!