The trick to ebay is to be patient. Some sellers want a fortune while other just want to purge their collection of unused products. Save your search and watch for bargains. It does work! Also do not bid until the last few seconds. There are a lot of scammers and I did catch one. Some have friends bid on their products right after a bid goes in to drive the price up.
Another tip is bid in the summer. Most of us northerners do our stamping in the winter so less competition in the summer.