A record store in Fells Point, Baltimore, which can be found at 1616 Thames St, right out near the water. It's won The City Paper's "Best CD Store" award for many years in a row now, and while there are still speciality CD places, like Reptilian Records, most people in bmore go to The Sound Garden for their music fix.
The selection is very diverse; good selections of techno, punk, pop, rock, country, world music, and who knows what else. They also have a wide selection of DVDs, including a small and rather scattered anime section, and huge rows of cheap used CDs for you to pick through at your leisure.
Prices are sometimes shockingly low; I bought my Martian Successor Nadesico DVDs there for about $7 below the price charged by even the cheapest online anime stores. They also have a shelf of new CDs, all for $10. There is always at least half a dozen excellent CDs there, whether they be Weezer, early Nine Inch Nails, or Johnny Cash. Even the regular prices for new CDs are quite low, often only $12-$15, versus the $17-$20 one will often see at Record and Tape Traders. You can use your extra money to get a sandwich at the pit beef place next door.
You can listen to virtually anything in the store on the half a dozen CD players they keep around (with headphones, of course). If it's used, you can just pop it right in. If it's new, you can take it up front, and they will open a copy for you, if there isn't one already open. So you're never stuck with something you don't actually like. They can also order obscure stuff for you, just talk to the guys behind the counter.
Their web page is http://www.cdjoint.com.