OK, I live in another almost no-stamp zone and buy most of my material on
ebay and have been generally satisfied. I try to be careful about what I acquire. I too would like an explanation of how to recognize shill bidding. Frequently, you will see items where someone has put in about a dozen bids for an item at small increments.
If I notice that happening, I either stay away or, if it's something I really want, I bid my maximum price in the last few seconds to avoid having my bid pushed. Someone once tried to rationalize that bidding style to me but it didn't make any sense.