I know it's somewhere on diabloii.net.
For normal unique weapon to exceptional it's
ral + sol + P.Emerald + normal unique.

Exceptional weapon to elite is
lum + pul + P. Emerald + exceptional unique
(Ladder only i think)


Normal unique armor to exceptional is
tal + shael + P.Diamond + unique armor

Exceptional armor to elite is
ko + lem + P.Diamond + unique armor.
(Ladder only i think)

I know there is some for rare weapon/armor but i cant remember them.