If you've got the know-how or the blind freaking misguided confidence to build or even work on your own guitar amplifier, then St. Pete’s Watts Tube Audio is a place you need to know. Veteran local musician and tinkerer Kenny Watts opened the shop more than half a decade ago when his business selling parts on eBbay grew large enough to make him think he could grow it into a brick-and-mortar enterprise. Watts Tube Audio still does impressive mail-order business to one-time customers and loyal supporters all over the place, and has carved out a niche as a one-stop destination for Bay area sound-electronics buffs as well. From fuses, tools and tubes to full amp kits, circuit boards and everything in between, if they don’t have it, they can get it — often at a price that’ll have you cursing the big-box music shop’s markup. 3200 Martin Luther King, Jr. St. N., St. Petersburg, 727-388-3309, turretboards.com.