There are tons of songs that are 7-8 minutes long, but I stuck to song 9-10,11,12 minutes to over 20 minute songs...
So, here's my Top 10, in no particular order...
Lynyrd Skynyrd - Free Bird (Live Version!!) (13:50)
Arlo Guthrie - Alice's Restaurant Massacree (18:36)
Ten Years After - I'm Going Home (Woodstock) (9:43)
Iron Butterfly - In-A-Gadda-Da-Vida (17:02)
Yes - Close To The Edge (18:42)
Pink Floyd - Echoes (23:28)
Neil Young & Crazy Horse - Cowgirl in the Sand (10:06)
Grand Funk Railroad - I'm Your Captain (9:54)
Jimi Hendrix - Machine Gun (12:36)
Creedence Clearwater Revival - I Heard It Through the Grapevine (11:08)
Honorable Mentions:
Bob Dylan - Desolation Row (11:36)
Paul Butterfield Blues Band - East-West - East-West (13:13)
Deep Purple - Child in Time (10:20)
James Gang - Stop (12:07)
Peter Frampton - Do You Feel Like I Do (14:17)
Traffic - The Low Spark of High Heeled Boys (11:39)
Emerson, Lake & Palmer - Take a Pebble (12:31)
Neil Young & Crazy Horse - Down by the River (9:16)
The Outlaws - Green Grass and High Tides (9:45)
Also, there are TONS of long LIVE songs that are jammin', I could of listed