If you're playing on a UNIX/linux-ish system, and you're looking for a list of words (and not definitions/pronunciations) check in /usr/share/dict. Most systems I have worked on have /usr/share/dict/words which is a list of English words, one per line. (/usr/share/dict + grep makes an excellent scrabble cheating tool, by the way :)

You might also want to check out the Lingua:: modules in CPAN. There may be something in there that you'd find useful.

Alan