A Google search will provide you with the information you are seeking and information that you never knew you wanted. That's what happened when I Googled Mr. Clean's first name, an article written by CNN titled: Real Names of 23 Fictional Characters popped up and I was trapped by this useless but fascinating information.
Here, are a few of my "I didn't know that moments..
Barbara Millicent Roberts
Ken Sean Carson
Schulz has said in several interviews that he named Peppermint Patty after a dish of peppermint candies he had in his office, and simply thought the name too good to pass up. (Source)
Bull from the comedy series
Night Court. His characters
name was: Nostradamus Shannon (Source)
... before eating his first cookie his name was Sid (Source)
Jonas Grumby was the Skipper
on Gilligan's Island
The Man in the Yellow Hat
he doesn't have a name in the books,
but when the movie came out we found out
he is Ted (Shackleford) the last name
was deleted from the movie before it's release.
As the adage goes, you learn something new every day. This new information is probably useless, except if you are in a trivia contest, but it sure was fun to find out.