Do you use My eBay, Pete? That's a big help in tracking both what you're selling, what you're buying, and what you're waiting to snipe. I've never found it necessary to buy commercial software to keep track of bidding and selling. I seldom list more than 25 a week, though.

In addition to My eBay, I do print out a copy of every auction I win and every one of the lots that I sell. These stay in a stack on the desk till either the merchandise or the the money comes in. When they come out of the stack, I leave feedback and toss the paper. All the auction responses from eBay and the buyers/sellers go into a folder in my email program so I have an online history after eBay erases theirs (30 days?).

I also keep a journal of auction lots sold or won. This is done by hand because I find it easier to scribble things on paper than to keep an automated log. I check these off when completed, and occasionally review the book to see if there are any slow pays or merchandise not delivered on time. There seldom is.