For in-ears, I have some sure e3c's and e4c's. Got the e4c pair at Comp USA when they were closing down stores for only $120, so I got a steal there. The e3c pair was a Christmas present from the wife. She bought them from
B&H for a fair price. As for the big guns, I got lucky...
There was an estate sale up the street and there was a pile of maybe 6 to 8 pairs, all different brands. They were about five bucks each. I don't think they knew what they were selling. AKG, Stax, Grado, Sennheiser, etc... I picked up three of four pairs at a fiver a piece, then looked them each up on the net when I got home. The worst pair sold for over $150 and others sold for $200-$300 each.
This old man was obviously into sound quality (and smoking, since they STILL smell a bit like old smoke). I use the AKG pair the most. They sound pretty nice - especially for five bucks!