Dawn of the Emperors added the Forester and Rake.
Emirate of Ylarum added the Dervish.
Alfheim split high level Elves into Lods and Wizards.
Rockhome added Dwarven Clerics.
5 Shires added the master sub-class for halflings.
Minrothad Guilds the Merchant-Prince.
Thar added the humanoids.
Darokin added the Merchant.
Golden Khan added the Shaman.
Shadow Elves added the shadow elf and shadow elf shaman.
Atruagan Clans another shamen, the Shamani.
Tales of the wee folk added a lot of Fae race/classes.
Top Ballista the same for flying races,
The sea people for sea races,
And night howlers the same for were creatures.
Hollow Earth had a lot of variations for the races who lived in there too.
GAZ8 (The Five Shires) had another version of the Halfling class but I didn't compare the changes.
GAZ9 (The Minrothad Guilds) had the Sea Merchant Class.
GAZ11 (The Darokin Republic) had the Merchant Class.
GAZ12 (The Golden Khan of Ethengar) had the Shaman Class.
I think there was some kind of Ranger class (the Forester, IIRC) somewhere too (maybe in Thyatis, in Dawn of the Empires).