Chris Burroughs (The Beep Goes On) Has put together some really nice Target I.D. Spreadsheets and E-Trac, SE Emulator Files as well as E-Trac Pattern Files. Heres the link, if you want it. http://www.thebeepgoeson.com/index_downloads.asp
The E- trac Emulator is very realistic, for those who are thinking about getting an E-trac but wonder about the tones. It's worth the download. There are many coin, jewelry, and trash targets to test, and you can change the settings just like on the actual detector. There is a link to the download on the site that Dave provided.