Bill Cosby is a well-known comedian, actor and author, and has been known as a personable, reachable celebrity for decades. If you want to reach out to Mr. Cosby as a fan, he has accounts with social networking sites like Facebook, MySpace and Twitter, where you can follow or friend him and respond to his comments. If you prefer the old fashioned method of sending a fan letter through the mail, he has a specific address just for that purpose. If you want to send him a letter for a different purpose than fan mail, you can send it care of his talent agency.

Step 1.

Place your letter in an envelope with a minimum size of 8 1/2 by 4 inches. If you want to request an autograph, include a photograph or stationary along with a self-addressed, stamped envelope. This envelope should also be 8 1/2 by 4, with your name and address on the front and a stamp in the upper right corner.

Step 2.

Write the following address on the envelope if your letter is fan mail:

Bill Cosby P.O. Box 4049 Santa Monica, CA 90411 USA

Step 3.

Write the following agency address on the envelope if you're sending a letter that is not fan mail:

Bill Cosby The Brokaw Company 9255 Sunset Boulevard Suite 804 Los Angeles, CA 90069 USA

Step 4.

Write your return address in the upper left corner and place a stamp in the upper right corner. Mail the letter.