You can get Aeris' limit, by fighting enough battles so that the last two digits of your battle count are the same number, ie 477 battles etc. and going to the guy in the cave near Mithril Mines, and talking to him, he'll give you a Mithril, take it to the weapon maker on the peninsula of the Gold Saucer, and he'll give you the option of opening a small or large chest, choose the small one and you will get the Great Gospel manual.
*puff puff*

I suppose you could have Cait Sith's last Limit Break...xD