Yes there's a bar that fills up under the top left of your HUD.
Also, you get EXP for participating in a battle, not giving it the last hit. Just like when you do battle in FFX, just by giving the monster 1 hit, magic spell, or healing you've participated in the battle... so you get exp. It's shared... :sweat:
EDIT: In EQOA you didn't even need to touch the monster your party was fighting, just be close to them (like stay in the same zone) and you'd get exp. I'm not sure if FFXI is like that... where you can leech off a party. It works great in low levels because if 4 people party up and fight different easy monsters that give 100exp each... you get 100 exp everytime you kill something, and give 100exp to everyone else in your party, aswell as get 100exp for every monster they kill. I think I did that for 3hrs and I went from lvl 5 to lvl 10.

This is besides the point though... hehe.. :sweat: