You will piss your pants laughing at these.
http://www.ebaumsworld.com/morepranks.shtml
These are calls made using a celebrity soundboard. Links to those soundboards (that you can make your own calls with, hehehe) are in the small text below the actual calls.
Twoof the most hilarious ones...
Miss Cleo #1 (all of them are VERY funny)
Full Metal Jacket #4