After much difficulty, I finally got the install page working and signed up for wordpress on my site: juliaritchey.com. I got the e-mail from wordpress confirming my new site and login. I then did the automatic upgrade on the dash to 3.03 after signing in and navigated away from wordpress for a short period. Now when I try to return to login I get the same error 404 page I've been dealing with all week before install.php started working. Any advice is greatly appreciated.