There's a lot of good info in
this thread.
We're lucky to have many world-class luthiers here in L.A.: Lemur, World of Strings, Stein on Vine and Los Angeles Bass Works are the main choices. There's also Hammond Ashley in San Diego if you're going to be that far south.
And if you're seriously looking for a new bass you should check out The Bass Cafe in Phoenix - they have a good selection at very reasonable prices.
Andy