I have done several cross country trips and will make reservations for national parks since they fillup fast in summer. Most other stops I do on the fly with no reservations and rarely have a problem. I generally use a campgound directory and call ahead in the morning for a reservation that night which gives me flexibility in routing and timing. being retired, we generally take a month to go cross country and a month back with another month on east coast. I decide what is comfortable for driving distance then look for attractions within that range. If you do make it to Goleta, Lake Cachuma has a good county campground.
