In Keychain Access for Snow Leopard, I clicked on Never for This Site for several sites before I figured out that Keychaine is a good thing. How do I undo this so I can save Login Names and Passwords for this sites?

I am using OSX Snow Leopard. Being naturally paranoid about password security, long ago when I first bought my Macbook Pro (my first Mac, in fact), I clicked never for this site over and over in Safari when asked if I wanted to save Login ID and Password info. I finally turned off the feature altogether in Safari. I have now come to my senses, and have turned the feature back on in Safari and added Keychain access to my toolbar. However, I have been unable to figure out how to get sites I previously pooh-poohed to ask to save password info. I have tried manually adding the site info to Keychain Access. I don't know where to go from here and after hours of searching have found no helpful posts out there. Is there a fix or do I have to reset Keychain Access completely to the factory default and start over?