I LOVE Truckster! It gives me wonderful information, truck stops, fuel prices, walmarts, rest areas, weigh station,restaurants, scales and more. You can search by state, or it can find the ones nearest to you at the moment. It also has a spot for notes, public or private, It has been a real life saver!!!
I just mentioned that app in another iPhone thread. Like I said there, at $2.99 it's a whole lot cheaper than a truck stop guide book and has a lot more information.
Found one called 'truck stops' on the android marketplace, it sounds the same from the description and also is $2.99.