We really enjoy Snow's Garden center for their plant and tree selection. They have a wide variety of items, and everything they have is in great shape. Their staff, overall, is really educated about plants.
That said, we ordered mulch there once and ended up with topsoil. It seems there may have been a language barrier, but that was rather disappointing. The good news is that we paid for mulch and the topsoil was actually more expensive. :)