Today marks the 60th anniversary of the 45 rpm record. RCA/Victor put out the first one, Eddy Arnold's "Texarkana Baby"
(She's my Texarkana baby/ Do I love here? Lawdy, lawd / Her pappy came from Texas / and her mom from Arkansas) with "Bouquet of Roses" on the B-side, on March 31, 1949.
As far as tangible media goes, it's still the cheapest, best way to amass a large and awesome music collection. Particularly if you're lucky enough to have a jukebox*.
You'll find 45s, often a bit scuffed and scratched, anywhere old things are sold, but if you're looking for more pristine and specific releases, go see Bill Eginton at Arkansas CD and Record Exchange. He's got the best collection in the state. Some 100,000.
I got my prized 7 inch, the Goodees "Condition Red," there.
*Still hunting a jukebox repair man. Suggestions?