If you are on the prowl for certain items, you can set up automatic searches that will alert you when those items go up for auction. I took a look at the automatic search features on iTrack.com, Bidders Edge and eBay.

ITRACK.COM
iTrack.com offers 5 free searches ("patterns") with a choice of 14 auction sites. When you choose the free option, there will be "occasional special offers and advertisements in your iTrack email updates." You may sign up for a 10-pack for $25/year or a 20-pack for $50/year. http://www.itrack.com

You can set up the alerts to be sent every day; every other day; or every third day, and you can choose to get the email updates in HTML format or text-only. Here's a list of the auction sites that are offered:

Amazon.com Auctions, Auctions.com, BoxLot, Ebay, Egghead.com, Gold's Auctions, Hassle Online, MSN Auctions, OnSale by Auction, Ubid, Upstate Auctions, Xoom Auctions, Yahoo Auctions, ZDNet Auctions

BIDDER'S EDGE PERSONAL SHOPPER
The biggest drawback to using Bidder's Edge is that it does not track auctions offered on eBay. To set up an alert, go to http://www.biddersedge.com and click on Customize My Search. Enter your search term and choose how you would like to limit the search. You can limit by: auction site, auction type (merchant auctions, person-to-person auctions, or group buying items), category, "new items only" or closing time (30 minutes, 1 hour, 12 hours, 24 hours, 48 hours or 72 hours). If you think the results of the search are what you want, click on "Add this to my Personal Shopper" located at the top right with two hands shaking in a green background.

Bidder's Edge searching allows you to choose all the auction sites or one at a time. So if you want to choose five sites, you have to conduct five searches and add each one to the Personal Shopper list.

While Bidder's Edge does not track eBay, it does offers a choice of 100 auction sites. (Eight of the 14 sites that iTrack.com offers are not offered by Bidder's Edge.)

EBAY PERSONAL SHOPPER
eBay Personal Shopper offers alerts for eBay auctions only, and saves a maximum of three searches only. Go to http://www.ebay.com and click on Search, then Personal Shopper. The first time you use Personal Shopper, eBay warns you that it will send your email address and search criteria information to NetMind Technologies Inc., which actually provides the service.

Click on Add a New Search. Choose item title or item title & description, then choose a price range. You can choose to have email notifications sent daily or every 3 days. (Email notification is limited to 30, 60 or 90 days, after which you'll have to set up the alerts again.) Preview the search and then click Save.

There were a lot of auctions from other countries; it would be nice to be able to limit by country.

SUMMARY
Of the three alert services I tried, I liked the HTML version of iTrack.com the best. I could track auctions on eBay AND Yahoo Auctions and other sites as well. And the email alert was nicely formatted and easy to review. Try them out for yourself and see which one works best for you.