Tell him to look at Auton and Inca's websites, then just do a keyword search for plasma TV lifts. This is not a new idea, and there are tons of commercially available products. He might want to talk to a custom installer about doing the work since if he can't even find a lift, I'm assuming he may not have the know how / ability to do the install work. No offense intended there.
Keep in mind that lifts don't always care if they are right side up- he may end up using a piece designed to lift a plasma out of a cabinet upside down to lower it...
http://www.inca-tvlifts.com/plasmaindex_tvdropdown.htm
If that lift won't do it for some reason, give me a better description of the room setup, etc. -- "rise up into a recess on one wall" is a little weird-- either it's going to rise at an angle and enter the wall, in which case you are SOL, or it's going to rise into the ceiling, in which case the lift above will work, or he wants to build a false wall portion out to house the retracted TV in which case the one above will work.
Keep in mind that lifts don't always care if they are right side up- he may end up using a piece designed to lift a plasma out of a cabinet upside down to lower it...
http://www.inca-tvlifts.com/plasmaindex_tvdropdown.htm
If that lift won't do it for some reason, give me a better description of the room setup, etc. -- "rise up into a recess on one wall" is a little weird-- either it's going to rise at an angle and enter the wall, in which case you are SOL, or it's going to rise into the ceiling, in which case the lift above will work, or he wants to build a false wall portion out to house the retracted TV in which case the one above will work.