The person that has THE ULTIMATE GARAGE....Ultgar....he sells water filters, although if I remember correctly it was either an arm or a first born in cost.
You can get standard water filters even at WallyWorld, that filters out particulates along with charcoal filters that will help with any odors, but I'm guessing that you are wanting soft water for washing the cars?
What about looking into a small water softener, then something like a couple of the whole house filters mounted to a board. It should be fairly straight forward to hook something up, that would last through a lot of washings.
You may also look at Griots Garage, as I do believe that he would have what you are looking for. I haven't received a catalog in a while, but I'm almost positive he has what you need.
