Although his writing style isn't always consistent, the book is totally worth reading just to get a clue on how 'cyber criminals' (used to) operate on a global scale. I said 'used to' because the facts narrated in the book occurred mainly in 2009-2011, but in the final chapter there is also some recent events.

Although the title refers to the spam problem, It's not just about spam itself, but it gives a full image of the surrounding cybercrime environment. Give it a try ;)