Mostly online (eBay, here, Stringbusters, Axesrus, WD, Allparts), because the two shops here try to be all things to all men and that means bass gets squeezed into a tiny dusty corner of the shop. Have been known to buy strings locally and that's about it. Yada yada support your local shop and all that but what if they don't really support me? I'm always so underwhelmed when I go in that I rarely do so, and to be honest apart from the occasional "must buy strings now" moment (which can be alleviated by having a spare set in advance), I probably wouldn't miss the shops if they disappeared.