Forum Moderators: buckworks
It would help us if we knew more about what you want the search engine to do. If all you're looking for is a basic search engine - i.e. the user enters some keywords and the engine returns a list of possible pages then you can go to any script site and find a number of search engines to choose from.
If what you're looking for is a more detailed selection tool, like a tool that will allow the user to select different criteria or drill down through increasingly selective categories, then you're really looking for what we call a winnowing tool. And these are usually custom built based upon the particulars of you store.
If it's somewhere in between, tell us a bit more about it.
Another thing we'll need to know is what script language you're working with or does it matter?