Recently I've discovered a really good resource for downloading live recordings of bands. Etree has been around for a long time on the internet, helping to facilitate the trading of live concert recordings. In the past, all the distribution has been done either via (very crowded) ftp servers or by sending CD-R's via snail mail. Well recently, with the increasing popularity of the BitTorrent p2p protocol, they've started up a BitTorrent tracker for trading/downloading live shows. You can find the tracker here. I've been having a ball lately exploring new bands, and listening to live concerts of my favorite bands. Check it out!
Oh - and if your going to be downloading any shows, I highly suggest the excellent BT client, Azureus.