If anyone is interested in the logistics of the cocaine trade I recommend the Dark Alliance book [1]. The book argues that when cocaine first appeared in the US it was not considered so dangerous or addictive and the authorities did not respond to it as a serious threat (at the time it was PCP that was being demonised).

[1] http://www.amazon.com/Dark-Alliance-Contras-Cocaine-Explosio...

For interesting reads on the politics of cocaine, in addition to the mentioned story in Freakonomics, take a look at:

Dark Alliance by Gary Webb: http://www.amazon.com/Dark-Alliance-Contras-Cocaine-Explosio...

Snowblind: http://www.amazon.com/Snowblind-Brief-Career-Cocaine-Trade/d...