| You'd need to take the certification classes through a Digidesign authorized pro school. You can't access any of the course material after 101 unless you're signed up.
With regards to if it's worth it or not is really up to you. If you are able to work at it and reach the expert level, you'll know more about the operation of PT than 99% of operators out there, but it will really boil down to whether or not your potential employer gives a shit or not (Narcoman being an example of someone who doesn't ... him and I have spoken in depth in a previous thread about this very topic!)
I'm certified, and it has given me tons of opportunities. However, it's an exception to the rule, and only one small piece of the puzzle.
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