What?!? The PCAT has a Vocabulary section now?
jk.
I believe you are asking for the best guide to use in developing your vocabulary for the PCAT. I know that there are vocabulary builders online that you can use. The following are the ones I used when I was preparing for my GRE.
http://www.soundkeepers.com/GRE/ GRE vocab builder with multiple choice quizzes
http://supervocab.com/ another GRE vocab builder with quizzes
http://www.sheppardsoftware.com/web_games_vocab_sat.htm Word games (mainly for the SAT, but useful)
http://www.english-test.net/gre/ Useful site. Find words by meaning, and find meaning by words.
http://rhettmaxwell.org/studyguide/gre/vocabulary1.php Quizzes
Others:
http://www.sparknotes.com/testprep/books/sat/chapter7section6.rhtml 1000 words for the old SAT