Only ONE way to track a letter with Post Office

I've learned a lesson today about tracking a letter with the U.S. Post Office. I recently sent a check by certified mail, and was told I could see the progress of it nightly online at http://www.usps.com/ by typing in the 20 digit tracking number. WRONG. You can only see when it's been delivered. "Delivery Confirmation" doesn't show you anything different either, despite what some Postal clerks have told me. I called 1-800-ASK-USPS, and was told that only the $16.95 Express Mail service can tell you where your letter is each day.
SO, certified and delivery confirmation is useless to track something. Further, if you're sending a CHECK for paying something off, either send it Fed-Ex, or USPS Express Mail. Otherwise, "it's somewhere in the system and we can't know where it is until delivery," said the Post Office Rep. Wonderful. So, after 7 days, I'm STILL waiting for a certified letter with a check to arrive at its destination. The Post office is no help.