AAA has a trip planner package that includes whatever it is that you need (play grounds, hotels, zoos, etc). I have also heard from a coworker that their GPS unit has the ability to click on "restaurants" (and perhaps other options) to see what is close while you are on the road. I do not have one, but for a long trip I would buy a GPS. Go to BestBuy and ask the GeekSquad what you asked above and they should be able to help you. Or get an iPhone which has restaurant finder apps and I believe even playground finder apps, etc.
Here is a website with application you can buy for your GPS:
http://www.roadsideamerica.com/gps/