The Healing Lorecall spell in Spell Compendium (and at least one of the Complete books, forget which) is level 2, and to get any use of it you'd need 5 ranks in heal. If you have that many, with any healing spell you cast (even cure minor wounds!), you can also remove a condition, fatigue being on that list. The spell lasts for 10 min/level. With more ranks (10 or 12, I forget) in heal, you can use healing spells to remove exhausted. If you don' want to prepare the spell, it's low enough level to get in wand or scroll form for cheap.
That's the easiest way I know of to handle that problem. There are other means, I'm just drawing a blank right now.
I know a Horizon Walker with the desert terrain mastery is immune to fatigue.
The Goliath bard prestige class in Races of Stone (Dawnsinger?) gets a bardic music ability to remove fatigue.