Don't waste your money on guides. They're sorta rip-off's if there's nothing spectacular to unlock.
All you have to do for this game to unlock stuff is:
It's not hard. Also for moves and w/e, you can find any guide or any hints/ things on moves, etc. on sites like cheatcc and whatnot.
TOTALLY not worth the buy
I remember getting the official guide for Final Fantasy IX back in the old PS1 days. Every important piece of information in the guide just referred you to a website to get the answer. It was infuriating.