For the usefulness of each skill, see the manual that comes with the game
(also available while playing through the '?' key).

       Skill                How to learn it (if learnable)
 Alchemy
 Alertness
 Appraising
 Archery
 Athletics
 Backstabbing               Bart the gladiator for Gladius
 Bridge building                 Carpenter or his book
 Climbing                    Master Thief to guild members
 Concentration
 Cooking
 Courage                       Barbarian to non-chaotics
 Detect Item Status
 Detect Traps                Master Thief to guild members
 Disarm Traps                Master Thief to guild members
 Dodge
 Find Weakness              Bart the gladiator for Gladius?
 First aid
 Fletchery
 Food preservation
 Gardening
 Gemology
 Haggling
 Healing           Jharod for non-chaotics, Mad doctor for chaotics
 Herbalism
 Listening
 Literacy            eat literate corpse or do Dwarven elder quest
 Metallurgy
 Mining
 Music
 Necromancy
 Pick locks                  Master Thief to guild members
 Pick pockets                Master Thief to guild members
 Smithing                            Dwarven smith
 Stealth                    Master Thief for guild members
 Survival
 Swimming                                Blup
 Tactics                    Bart the gladiator for Gladius
 Two weapon combat          Bart the gladiator for Gladius
 Ventriloquism
 Woodcraft

All skills can be gained through a wish (I capitalize the skill name, just
in case), except for healing (which just heals your character), and
alertness (which increases your perception).

   If you can add to this list, or correct anything, leave me a note, or
                                e-mail me.