Well ive never experienced that much reduced sets aswell. All the tricks I use (ebay, Canadian shop at home) mostly end up as pain in the megablocks. The american custom pick up randomly packages and make the guys pay the taxes : with my overwhelming luck, I've been caught already two times, so with taxes + shipping, I could have found cheaper on bricklink ^^
But fortunatly some great deals appear sometimes.
Anyway, I still prefer to pay full time than waiting for the set to go on clearance :-D