"Drug, Set and Setting" by Norman Zinberg is another classic. Andrew Weil has talked about it (search YouTube). His thesis was on nutmeg as an addictive drug. Almost anything can be addictive given the right setting.
"Addiction is a Choice" by Jeffrey Schaler. Saying it is a choice is not at all meant to cast blame, but to emphasize that to use drugs is a choice given one's life circumstances, and is influenced by many variables. To focus on the drug use itself is to neglect real "problems of living" (as Thomas S. Szasz called them). By viewing it as a choice, one is also empowered to end their addiction, but it must be voluntary and not coerced by family members or the state.
I sometimes think of unhealthy addiction as being trapped in a local minimum of pain -- given limited resources, including limited personal strength to change the circumstances or environment one is in (e.g., job, marriage, housing), then addiction to a substance, or even a non-drug activity, can become a local minimum of pain, all avenues out of which produce, short-term, more pain than the status quo.
So it can be philosophically argued that addiction is a rational decision given the circumstances and the resources available. The key to successful addiction treatment is not behavior modification or "education", but providing resources so that one may escape local minima, and without punishing them for any behavior which does not harm others (hurt feelings doesn't count).
If the drug use is focused on and punished, even criminally, it never addresses the underlying issues which led to drug use being an escape from pain in the first place.
In the current system, harsh punishment for drug use, or paternalism over one's life in the name of "protecting one from himself", becomes more important than the principles of improving happiness or avoiding coercion against fellow humans.