Reading the Apocalypses and Exegeses is definitely helpful. There are five apocalypses and four exegeses so far. You can read the Apocalypses, Exegeses, and, if you're inclined, the synopses. (Though there's only one synopsis so far)
Perl 6 and parrot are, while closely linked, separate. Currently Parrot can use the help, unless you're in a position to duplicate Larry, which is the only way that perl 6's design will go faster. (If you consider the perl 6 parser/compiler separate from parrot, though, that's cool--we're working on that project as part of parrot)
The docs and testing for parrot are underway, and part of the parrot kit. We do, of course, always need more tests, more docs, and more general thumping
Folks of all skill levels are welcome. You don't need to be a whiz at C, or Perl, or English, though any one of the three is certainly useful.