Camping / Hospitality organisations in the US
I travelled Dallas - Los Angeles - Vancouver - Alaska in 2002 but by motorcycle. I camped as much as I could.
The cheapest campsite I came across was in New Mexico which had it's own natural hotspring. There were no camp staff, just a little box with a sign asking you to deposit $3 for each night you stayed.
On the other hand in California I was gobsmacked at campsites that were asking for $30! Seems like daylight robbery.
It might be useful to bargain with campsites that are setup for full RV/mobile home hook ups as a lowly cyclist is unlikely to use these services.
I came across a few hostels and sometimes resorted to a cheap motel ($30) when night and bad weather were closing in and options were limited.
I've used
www.couchsurfing.com (but not in the States) and can highly recommend it. In Poland I met Gwenn (I'd only known for about 24 hours) and she gave me the keys to her flat while she went on a business trip to Norway! They have a vouching system to help prevent you meeting up with a mad axe murderer. You can comment on every host you stay with and every host can comment on you. By looking at a person's comments you can get somewhat of a feel for them. Also to provide more confidence a surfer or hoster can donate a nominal €25 to couchsurfing by credit card. You have to give your address as specified on your credit card. Couchsurfing then send a password by snail mail to this address which you enter into the website. In this way the anonymity of the web is reduced somewhat and you can be more assured of who you're be dealing with.
On Friedel's Travelling Two website she mentions..
www.warmshowers.org
www.hospitalityclub.org
There is also
www.servas.org
But I don't know much about these last three. Anyone used them?
There's also the option of wild camping just stopping when you find a nice secluded spot. One rule you should abide by is doing all your cooking/washing up at least 25m away from the tent - in fact you should probably do this even on a campsite. You'll invariably spill something and if not that will have empty food cans and other nice smelly things that will attract wildlife, in particular bears. You should store your food attached to a rope preferably hanging free from a tree so bears (and climbing bears) can't get it. Good campsites have steel bear proof food lockers - toothpaste shouldn't be kept in the tent either.
On one occasion when I was lazy and had left an unwashed empty can of chilli outside the tent I was woken up to slurping sounds just outside the tent - to this day I don't know what animal it was but I didn't want to open the tent to find out! On another occasion (this time when I was being careful) I came face to face with a black bear on a campsite in Stewart, B.C. - I was on my motorcycle, I revved it loudly and the bear took off!