I have found the best prices for etopps autographed cards by using certain search terms on ebay which you can save as a favorite and then get emailed if there are any new listings with these search terms for up to a year.
Here's my list of search terms for etopps autographs:
Try them and see what comes up.
After you do a search for each one, there's a link next to the search term called Save This Search. You will be given the option to have the search results emailed to you and you can choose for how long. If you subscribe for six months, days before it expires you will get an email from ebay asking you to re-subscribe. It's a great little tool to have.