Here's 2 sites:
http://www.salikon.dk/callisto.html
http://blackgate.morningstar.info/
Both of these deal with a whole new RPG that someone's developing for Ultima (fan site, I believe). However, a lot of the stuff comes up as "Under Construction."
Also, what Age are you trying to go for w/ the Ultima game? The races & classes available change greatly, not to mention the world map
.
For the Age of Darkness, it's humans, dwarves, elves, and halflings (you'll have to stat up the Fuzzies, if you want). Classes would include fighter, cleric, wizard, and rogue for the 1st 2 games, plus ranger, druid, barbarian, paladin, bard (called a lark in the old manuals), illusionist, & alchemist.
For the Age of Enlightenment & later, the classes available are bard, druid, fighter, paladin, ranger, and wizard. Adventurers/PCs of the tinker class could be handled as rogues. The shepherd seems to work as the Commoner NPC class--you may want to do something different, though, if Shepherd will be a viable PC class--maybe even a variety of the monk class! Only humans are available as a PC race.
As of Ultima 5 (and later, I think), there are really only 3 core classes: Fighter, Bard and Mage. Paladin, Ranger, & Shepherd are variants of Fighters (no spellcasting ability). Tinker is a variant of Bard (half spellcasting ability). Druid is a variety of Mage (full spellcasting ability). The variants of the core 3 classes could be Prestige Classes, if you wanted.
Also, by Ultima 4 & later, every spellcaster used the same base list (mages can heal!).
In all honesty, you may want to wait & see what Unearthed Arcana has to offer--a variant spell system, as well as a CoC-like base class which may work better at trying to capture the "classes/occupations" from Ultima.
However, in all honesty, I'm not sure what Ultima: Online is like at all. Then again, from what little I know, UO is essentially a bunch of alternate realities. It may be safe to say that, if your campaign is based after U9, all bets (and previous rules) are off--it can be standard D&D 3.5 from that point on, if you wanted.
Also, a question for hong: has your Ultima stuff been upgraded to 3.5?
Hope any of this helps.
