If you'd like to do them yourself online, just log into the Disney website (you will need to create an account if you don't already have one) and go to "my reservations." If your ADR isn't listed, there's a link on the right to search by confirmation number.
If you don't have the confirmation number, call the dining line since they can search by name/phone number.
As for transferring, check out some of the cancel threads in the reservations sub-forum - I don't think WDW allows changing names on ADRs anymore, so the best you can do (other than having someone use your name) is to coordinate so that someone is ready to snap up your ADR as soon as you release it back into the pool.