This is a fun area, as the DMCA, for its flaws included a loophole for non-commercial distribution of live concert recordings. The only requirement is that it isn't an exact copy of a commercial release. I am not sure about the exact standards, as live albums often aren't the entire concert. Here are some other sites where people share these tapes.

http://www.thetradersden.org/

https://sugarmegs.org/

http://www.dimeadozen.org/