What I'm Talkin' Bout: The Gary Coleman Story is Gary Coleman's book. Gary arrives at Paradise Mall on Tuesday to give autographed copies of his book to the townsfolk. One of the errands of that day given to the Postal Dude by his wife is to get one of those autographed copies. An autographed What I'm Talkin' Bout can be obtained both by waiting in line to get it from Gary, or by killing either a bystander who's already got their copy or Gary himself. The Postal Dude lies and tells Gary that the copy is for his mother. Gary sarcastically acknowledges this, and then proceeds to tell the Postal Dude that if he sees him selling the copy on eBay he 'will go to [the Dude]'s home and kick his narrow ass'. At the end of the day, it is revealed that the Postal Dude and his wife really plan to sell the autographed copy on eBay, and the Dude wonders if they can get more money from it after Gary passes.
- It is actually possible to obtain more than one copy of this book, as methods are not mutually-exclusive - Coleman drops a copy regardless of whether the player obtained it by standing in queue or not, and both police and Coleman's Crew are pretty lousy shots (Coleman himself may start chucking grenades), which makes it highly likely a couple of Coleman's fans would be iced in the shootout, making their copies available to be picked up as well. And of course, nothing exactly stops the Postal Dude from actually receiving the book from Coleman, then promptly wasting everyone around who's likely to have a copy of their own. Yield may be as high as five copies at once. Although you will actually waste your money, you can buy more copies on Wednesday from the Bank.
- The title of the book refers to the catch phrase of Coleman's most famous character, Arnold Jackson, from the late 1970s-1980s sitcom Diff'rent Strokes: "What'choo talkin' 'bout, [character to whom he is speaking]?". This may be a reference to the fact that Coleman never managed another successful role, further reinforced by the book's cover picture portraying Coleman as Arnold.
- It is possible to give Krotchy a copy of this book on Thursday in exchange for a Krotchy Doll. This can be useful if the player wishes to conserve their cash (since Krotchy will take all of what the player has on hand) or if they want to avoid the firefight with the mascot.