The Cigar Warehouse is OK. Since going through a change of ownership a couple of years ago, the selection of pipes and pipe tobacco has diminished. But if you're a Peterson fan, rejoice! The new owner is a Peterson rep, so there's a nice selection of Peterson pipes and tobaccos.
There's the Original Tinderbox in Santa Monica, which is a terrific store.
Not a whole lot else left. LA used to be nirvana not that many years ago. But while it's still great for cigars, pipes are almost an afterthought.