Well, there are also sites like cruisingforsex.com where you can get listings - in great detail and with comments - about where to go to find the cruisy spots just about anywhere.
Obviously there are also chat rooms on gay.com, etc which cater to people looking to hook up, sometimes at a cruisy spot, sometimes not.
I've tried to go to rest areas and such for public anonymous sex, but I can't ever seem to do it, I guess I'm not up for the anonymous encounter.
I just took a look around that cruisingforsex.com site. I feel like taking a shower in Purell.
And I have to wonder how much of the online stuff is really law enforcement trying for some kind of entrapment.