Wolfgangs is great. Curious about their format, though. Why are only some shows available for purchase?
Here is another "concert vault" site that is well worth checking out. Bit of a different format; only certain shows are available for download at any given time, but the shows are usually excellent, tracked, and artwork is also down-loadable. They will also provide a link for archived shows that are not currently available for download upon request:
www.bigozine3.com/rarities/