+1 to what everyone said above.
all the online sites offering ACLS cert without a in-person/live skills test are non-AHA. Most just have you sign a form saying you've done the clinical stuff at work. If you're going to pay, you might as well pay for the real AHA ACLS card.
If your ACLS is not expired, you can go to a recertification course that takes one day.
If your ACLS is expired, they make regular people retake the 2 day course. One center near us offered us a "Challenge" course since we were all anesthesiologists, and that takes up one morning only.
If you can't get the Challenge course, the neat thing is that AHA now offers a CD + live-skills-testing option called Heartcode. The CD takes a couple of days to do, but it comes with the electronic AHA book (don't buy the stupid paper book) AND you get 12 CME units! And you only have to go in for a short skills test.
Since there wasn't a PALS challenge course for us, my group opted to do the PALS Heartcode CD at home, then on one Saturday morning, we did an ACLS challenge course followed by the PALS-Heartcode skills-only test, and done by lunch.