spheres

where is the best place to get power / mana / speed / ability spheres? i have the airship. thanks.

Get Kottos in the Monster Arena and use a distiller on it. You get 40 of the type of distiller.

Failing at the Monster Arena, you can also fly back to anywhere previous in the journey for spheres. Now would be a very good time to level grind (Zanarkand and Gagazet seem to do very well as practice).

If you have the airship, and depending on how far you got in the Monster Arena, you may wish to do that sidequest. Not only will you get the spheres you need but starting at Besaid and working your way back, but you will get easy ap, weapons, gil, etc.

You can also get items you may have missed. Revisit the temples and trials also, if you never had before, to get a nice surprise.