I'm a planner, so I plan out my stops ahead of time. Looking online for places to get diesel, where I have a bit more confidence in what I am getting (BP, Shell, etc.).
Once I decide on a place to fuel, I double check it online, getting down to google street view to try and get an idea of the layout of the station. It helped a lot during my last 4800 mile trip.
Also helps to have a 38 gallon tank. Gives me lots of leeway.
BTW, I detest Pilot/Flying J. 80% of the time, my card doesn't work or prices at the truck pumps are higher than the car pumps. Lousy kept stations and brain dead help. But, sometimes they are still the best option (and isn't that sad).
Oh and don't just rely on the Major stations websites to tell you of what stations they have out there. The Pilot book missed several stations (not even online) and the BP online was a total joke. Must have gone by 20 BP stations in the UP of Michigan that were not listed. Gasbuddy is your best bet.