Easy Guard Sources!

[Peter_20]

You might already know about this, but I´ll tell you anyway:

First, you need the Airship and Yuffie in your party.
Equip her with the Conformer, and give her the "Master Command"-and "Mega All" Materia.
Now, head for the badlands close to Mideel and start running around (Enemy Lure is really helpful).
With luck you´ll find the Spirals (I think that´s their name).
Now, simply have Yuffie attack ´em all with the Morph Command.
She´ll kill everyone, and you´ll end up with two or three Guard Sources, after one battle!
I got about 20 of them in a few minutes!
This is an incredibly useful strategy and will beef up your chars in no time!