A Hanshin Tigers Game at Koshien Stadium
Also outside are several plaques honoring retired Tigers:
There's a Koshien Stadium Museum, which is certainly worth checking out. Unfortunately, I didn't. That makes at least two museums I've missed, including the Sadaharu Oh Museum in Fukuoka.
Access is quite simple; take a Hanshin Main Line train to Koshien Station. Coming from Umeda Station (essentially Osaka's main station) express trains take only 12 minutes and local trains take 22 minutes. From there, it's a couple minute walk south; the stadium is literally just past the expressway overpass, which runs within meters of the stadium. Be sure to buy your return train ticket before leaving the station, because lines will be long on the way home. Or use a Suica or other pre-paid train fare card. Tickets should be bought well before the game, especially for weekend and holiday games, but same-day tickets are usually available on weekdays. Remember that you can buy tickets at convenience stores all over Japan, though you'll probably need assistance from a Japanese speaker. Employees have been willing to help when they aren't busy.