multi site/pro site registration signup form

I am trying to replicate the signup workflow that you use with edublogs.com. I like letting the user be able to create their username, password and blog URL/info on one screen. Using the wp-signup.php form even with pro sites seems very clunky. It is possible that I am just missing one of the needed plugins to accomplish this but I’m not sure.

Any ideas would be appreciated. If there was an option to allow the user to select a paid version during registration that would be even better but even getting it to function similar to edublogs.com would get me headed in the right direction.

Thanks!

Brian