I completely agree about the whole rip-off industry that has built up around ticket buying, and would second the opinion that Wegottickets are the best I've found when you have to use an agency to get hold of event tickets.

Their fee is actually 10% (not £2) so for instance a £9 ticket would have a 90p fee added, or 2 x £15 tickets would have £3 added. Their system is that you gain entrance by quoting your reference number (whether you want to print the confirmation or just write it on a bit of paper or whatever) so there are no postage charges. I use them whenever possible, and most of the small, intimate gigs I go to use them as at least one of the agency options.