Go to
Select Products - Car Audio Installation Materials
Click on Products, then in the search, type in wire loom. They take paypal.
I get my grille metal to cover amps and subs from them.
For JL wire, I went in their dealer locator.
California Concepts, 1020 Hansen Way, Redwood City
Auto Sound, 670 El Camino Real, Redwood City
JJ Audio Images, 1010 California Drive, Burlingame
Car Stereo Company, 4646 El Camino Real, Los Altos - Signature dealer status
Precision Auto Stereo, 21181 Mission Blvd, Hayward - Signature dealer status
One of these not only will have quality cable, but should be able to sell you a few feet of loom besides.