I seem to recall reading this in "Reagan: In His Own Hand" also.
Yes, the book can be bought in an audio format.
And Ronald Reagan did say everything that was in this thread's lead post. But the author(s) of the email infer that Ronald Reagan advocated the legalization of marijuana when he clearly states just the opposite.
Here is the exact preface to Ronald Reagan's addresses on this subject in the book:
In several radio addresses Reagan argues that marijuana is a dangerous drug and opposes legalization. But while emphasizing that young people should be made aware of the risks involved, he also says, "If adults want to take such chances that is their business."
Of course Ronald Reagan knew that even though it was illegal, many adults would still choose to smoke it.