Those small files are nothing but spam, so I would advise you don't download those. As for finding specific live concerts, you could try searching at different times a day or maybe try some Live bootlegs torrent site *note: Not sure they allow Limewire, so you might need to use a real torrent client. A few of the top of my head:
www.dimeadozen.org :: EzTorrent v0.6.4r284 ZOMB Torrents
If I remember correctly both of those should have videos.