"Take Me Out to the Ballgame" by Nordevco
I've done this puzzle a thousand times, probably. It's 500 pieces (18"x24"), so it doesn't take too long, but is good for an afternoon. The cool thing is that it came with a key to what it shows:
I picked this puzzle up from a Bits and Pieces catalog a long time ago along with another baseball memorabilia puzzle, which I'll show some other time. You can still find this puzzle on the internet (on eBay and such), but typically not unopened. Bits and Pieces does have another awesome baseball puzzle available right now, though.
I haven't looked up much of this stuff on eBay, but I know you can find several copies of the 1934 Goudey Jim "Rip" Collins card (No. 15 in the puzzle).
Hopefully I'll one day have a card collecting room that in which I can frame and hang this puzzle. Until then, I'll just enjoy putting it together every few months.