Originally Posted by MrSelfDestruct

First of all, don't buy from Crutchfield unless the alternative is lighting your money on fire. Home Depot or Radio Shack should have wall plates with a hole for a single F connector in the middle. Get them, either paint them to match the wall or leave them white, and mount them behind each speaker*. You'll have 2.5x4 inch hole to work with for fishing the cable through, and it will look nice and professional.

To actually get the wire where it needs to go, drill a 1/4" hole from the crawlspace up into the wall. Cut out the spot where you're going to have the plate for the cable, and make sure it's right next to a stud. Tie a pull string to the fish tape and push it up from the crawlspace, leaning it against the stud so it's easy to find (two people and a ladder cut this from a 20 minute job to a 3 minute job.) Hold the pull string while to pull the fish tape back, then pull the speaker wire up to the plate, leaving two feet dangling. Mount the plate with the wire coming through, mount the speakers, attach the wire, then push the extra back into the wall. Plug holes you drilled in the floor with fire-resistant, water-resistant clay or expanding foam.

* - you mount a non-load-bearing, low voltage plate on something like this http://www.erico.com/products/CADDYc...rcktsMtllc.asp
that's what we use for plenum cable runs at work, and I'm sure HD has something in quantities of less than 100.