Which browser(s) / version(s) / operating system(s) have you tried?
That's going to be the only help in making sure it gets resolved. There's
a chance the combination(s) you're trying to use may not have been tested
or may not be supported for one reason or another.
I can tell you that there's a lot of stuff that only works in IE (I hate
this, but it's industry wide... and it REALLY irritates the Apple people).
I've had random issues with viewing billing info unless I clear my cache,
and close everything and go back in.
Finally, if all else fails, you should be able to call Customer Care and
place the same order through the phone.