Camping between VT and CO in March
I am planning a 4-week trip from Vermont to Colorado and then to Arizona to see the desert next spring. Mid-March, when we want to start, is still winter in most of the Northeast and Midwest, so we cannot simply wing it like we did last September and pull in at camps and state parks that just happen to be along the way. We need to spend the first night around Cleveland, OH the second around Des Moines, IA. I know that most Walmart stores allow overnighting, and some truck stops along the interstate also have RV spots. Can anybody suggest an easy way to find what campsites or other camper accommodations are available along I90 and I80?
Thanks in advance.