we always found the state parks had more reasonable camping rates. get a current copy of "let's go USA", as well as a good current atlas with tour info. the national parks had a "silver eagle" (maybe it was a "golden eagle", one is for senoirs.) pass that i think are $100 now. this one pass will allow you to get in every national park or monument in the US for one season, or year, and is definitely worth the money.
we have enjoyed many national parks. i am really p!$$ed at how they have become such tourist traps, but i guess everone else wants to see them too. or maybe they're all coming now because they have better gift shops. carlsbad caverns was terrific, be there in the evening to see the bat flight. mesa verde and montezuma's castle. yosemite was a lot better before it was privitised, but still is awe inspiring (better if you do some hiking). grand canyon has some great primitive campsites without the crowds, (we stayed at a free site 100 feet from the west rim. ask a ranger not a tour guide) although there is a reason everyone goes to the south rim as it is a view (wow!!!!). hike to the bottom if able. crater lake didn't have much, but something touched me there (awe). some of the cities have some back alley tours that take you into the underground (see the old water, subway systems etc.). muir woods. yellowstone. dakota badlands. meteor crator. tombstone az. (there is also a huge copper mine down near tombstone that had worthwhile tours.) rozwell nm. most of the old military sights and forts on the east coast. taos nm, although i found the indians rather hypocrytical as they talked about how their villages were so sacred that it would cost $10 to take pictures. washington dc, philidelphia, crazy horse, mount rushmore, mystic seaport. new orleans (is bourbon st worth visiting again?), key west, st augestine.
we saw mt st helens 15 years after the blast, even with the new growth we couldn't believe the devestation.
also, i always wanted to hit that giant garage sale that goes on in the midwest somewhere.
