I'm not an RV'er but, since the economy chased me out of my Unix sysadmin gig, I resorted to putting food on the table by becoming a freight jockey (it was also a nice change of pace). When you're on the road for 26 days out of the month (as well as single with no children) shelling out rent for an apartment is kind of a moot point, so I literally live in the truck. Wifi on the road is really no big deal anymore, especially since most major truck stops, hotels, and even quite a few interstate rest areas now have hotspots.
That being said, there are a few things I do to make online life a little easier for a road warrior:
(1) As I already mentioned, many of your typical diesel stops are going to have wifi but the network can get pretty crowded at times. Some of the best times to use wifi at these facilities is 9 am to 5 pm, when most of your competition is going to be on the road instead of hogging up the bandwidth.
(2) The signal coverage in the places can also be a little spotty: one corner of the lot may have wonderful signal strength but another can absolutely suck. If you can, park so that you can have a clear line of sight to the building in which the antenna is located. Also, try not to put the fuel islands between you and the building if it can be helped; you can go from a really good connection to being knocked offline because somebody's Peterbilt pulled in to the fuel lane at the wrong time.
(3) Many of the wifi hotspots in these stops are managed with OpenDNS and certain websites will be blocked (namely, anything having to do with torrents).
(4) Wifi obviously won't be available everywhere you stop. If you often find yourself in the middle of nowhere (like me) then consider getting something like Verizon's MiFi or Fivespot devices. Verizon's plans seem to be better for heavy users but, if all you do is surf or check email, then there are probably cheaper plans around.
(5) One of the best investments I've made was a wifi repeater with an externally-mounted antenna. A typical trailer is about 13'6" (4.5 meters) in height; when all the diesel jockeys park it for the night there's going to be a awful lot of metal for your signal to try to get through.
(6) I often use my laptop for trip planning as well as keeping my DOT logs via an approved logbook application, so my machine is often running while I'm driving (but I do keep both hands on the wheel and my eyes on the road). Don't know about RV's but trucks bounce around a lot; as you can imagine, this repeated shock-testing can't be very good for the condition of your laptop. If you're going to be doing something similar then I highly suggest getting a laptop stand which bolts to the seat (the seats are usually equipped with "air-ride" shock absorbers and can greatly reduce the constant jarring experienced while driving).