Get yourself a PC version and play the pocketstation.

It's the best way to boost your charcter.

And to get Elixirs...

Best way to get them is with Tonberry's Call Shop s Ability.
Get to the store
Estar????
And buy them there.
You can also refine them, with Med LVL Up.
And there's another way to find them, but details seems to slip me.

I'll edit this later, rigth now, I got a major headhache and don't want any replies till tommorow.

Hope I helped you.

Btw: Poketstation is the chocobo mini-game.
It's worth the extra time to get the items, if you want to waste it...
You can get Ribbons, a GF Ability (100% resistance to all status change), the only way to get it.