I spent a week in Nashville over the summer for a big show we were exhibiting at. It was my first time, and I loved it. Don't judge the place by the drunken tourists on the weekend. Dig a little deeper and you'll find that you can't throw a rock without hitting someone who's got talent. It's like Austin TX, but with more denim. It was July, hotter than hell, and all of the guys were still wearing boots, blue jeans and the mandatory stetson...
I went to Gruhn's (as Matt suggests) - they have some cool retro T-shirts, and I noted some cool basses (inc two Ampeg Dan Armstrong's), but all were righty.
I'm not really a country/western guy, but it's easy to appreciate the good playing you'll find in most of the bars. If you need an apres-beer Karaoke fix, Lonnies is a fun late night dive-bar (cash only) that's worth a quick visit:
http://www.lonnieswesternroom.com/There was a young blonde girl running the Karaoke who had the most amazing voice.. she was tiny but her voice could blow the doors off an F150. The place next door in Printers Alley, the Fiddle and Steel:
http://www.fiddleandsteel.com/ is a cool place to kick-back and watch a few bands. Very low-key, but the owner is super-cool, and a buddy of a friend of mine was the opening act one night during my time there. Beware that many bars have a cover on the weekend. At some places it's up to $10. I don't mind paying a few bucks, but $10 is getting into serious beer money. If you need a break from the C&W, there's a hard rock cafe...it's the typical set-up, but makes for a break in the routine, and the food is ok. Speaking of food, you need to go to Jacks:
http://jacksbarbque.com/It can get a bit touristy, but the BBQ is great. It's cafeteria-style, and I ate there 3 times in a week. I was 5 pounds heavier when I got back (no word of a lie).
For other guitar stores, I wanted to check these guys out, but did not get time, and did not have a car:
http://www.worldmusicnashville.com/Have fun!