The entire issue with a few vocal collectors in the west is that they want to hunt on public land and that's been illegal for years... Those collectors that hunt/dig on private land have none of those issues. (There are other issues, like the Kentucky bill, but they aren't nearly as bad or as far reaching as the federal laws.)
I feel for collectors out that way, especially if they been hunting sites responsibly for years, but the laws are pretty clear and surprisingly old (dating back to 1906.) Since the government started focusing and training field staff on enforcing the existing laws, a lot of people who were doing what they've been doing for a long time have been caught. Some of them were really just innocent people who like to walk around outside and pick up arrowheads, others trespassed on Indian reservations and looted burial caves and other sites still visited/mantained by the tribes out that way. The bad apples tainted it for everyone else.
If anyone wants a pretty decent overview of the archaeological laws that affect collecting on public land, check out this slide show presentation. If you can't get in, try again tomorrow it just means we've gone over his bandwidth limit.
http://www.fws.gov/historicPreserva...tectionAct.ppt#277,1,Archaeological Resources Protection Act