Key trapped in ignition cylinder

In my exhuberance to end my journey, as soon as I parked, I went to shut off the ignition only to find the key would not remove fromt he ignition. I went to the Help manual--and it described the problem as "Key trapped in ignition cyclinder", probably because I did not wait until the shift was in "Park" before I tried to remove the key. I tried several times--but frustartion & heat were not helping, so I have locked the car with the alarm & the key still in the ignition. Any ideas for removing the key? Also, how much SHOULD it cost to have this done "professionally"?

Neon Dion