I've been using a nifty little program to delete individual entries in the address bar. It's called editurls.
You can read about it here
http://www.aandrc.com/editurls/index.htmIf this is something you want to try, click on download for the file. If you install it, make sure you choose the for all users preference.
After installation, open the program, click on the URL you want to delete, choose Delete Selected URL, and then click Save and Exit. If your browser is open, you'll have to close it out then re-open to see that the URL is no longer there.
I discovered this program when I also typed in a wrong URL and wanted to keep the list for a while longer.