Does anybody know if there is a JAA CPL practice or sample test anywhere on the internet?
Yes, but as far as I know you have to pay a small fee for them.
Also, if CPL(A) is written, does the A signify "airplane"?
"Aeroplane"
Are those questions from some question bank for each section? Or are they questions for each of the sections listed there, such as "Mass and balance" "Performance" etc. Or is that a sample test for the CPL?
Those are the learning objectives. There used to be some sample questions on there too which actually used to appear in the real exams....probably still do!