Rockies:
Win - "Rocky Mountain Way", by Joe Walsh
https://www.youtube.com/watch?v=UsEE5usGodQ
Loss - "Green Onions", by Booker T & the M G 's
https://www.youtube.com/watch?v=_bpS-cOBK6Q
Base Hit 1 - "Let it Rock", by Kevin Rudolf
https://www.youtube.com/watch?v=u0n4eMGXAyk
Base Hit 2 - "Strike it Up", by Black Box
https://www.youtube.com/watch?v=d_XI4FZ3wHw
Base Hit 3 - "Blitzkrieg Bop", by The Ramones
https://www.youtube.com/watch?v=iymtpePP8I8
Walk - "A Fifth of Beethoven", by Walter Murphy (this one is really only used for walks that load the bases, but I use it for all walks in the game, since that's the only option)
https://www.youtube.com/watch?v=0ouMaLRth-s
Homerun - USED TO BE "We Like to Party", by Vengaboys (they changed it last year, and I have no idea what it is. I still use this one)
https://www.youtube.com/watch?v=6Zbi0XmGtMw
Run Scored - "Sandstorm", by Darude
https://www.youtube.com/watch?v=2HQaBWziYvY
7th Inning Stretch - "Hey Baby", by DJ Otzi
https://www.youtube.com/watch?v=aNsmiqmaEWo
Clutch Out - "Palladio", by Escala (this doesn't seem to be the exact version that they use, but it's close. This is only actually used for bottom of the 9th/extras out while in the lead, but "Clutch Outs" is as close as we've got)
https://www.youtube.com/watch?v=qn_wlkzW1ds
I've heard both "Celebration" by Kool and the Gang, and "Kernkraft 400" by Zombie Nation for clinching a playoff spot, winning the pennant (the one time it happened), etc.