Hello,
Most of the information are in wManager.Wow.ObjectManager.ObjectManager.Me (or wManager.Wow.ObjectManager.ObjectManager.Target for the current target), by sample for the mana:
wManager.Wow.ObjectManager.ObjectManager.Me.Mana
wManager.Wow.ObjectManager.ObjectManager.Me.MaxMana
wManager.Wow.ObjectManager.ObjectManager.Me.ManaPercentage
But to test if an spell is usable it is more easy to use:
wManager.Wow.Helpers.SpellManager.SpellUsableLUA("Name in game");
(you can convert xml fightclasses to c# with "fightclasses editor" to get a codes samples)