A gig is NEVER sold out. Always some people selling tickets on the streets just before the gig. I even got in at U2 that way. They do ask some extra $$$ but you can usually agree on a price, they're just as desperate to sell as you are to get in
And I'm sincere here, not joking. In the past I sometimes bought second hand tickets via the internet but collecting them was always tough and they usually ask more than the original price as well. Buying them on the streets before the gig is just as easy, that's my experience. I tried it several times so far and it always worked.
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