^^ Great books. Also checkout the books about the lean startup by Eric Ries (there's like 3-4 of them now).
I would also recommend the ultimate sales machine. Even though I've only read 20 pages since I started reading it one month ago (yes, I run a startup), it's really interesting and helpful.
While I haven't read it (it came out after I'd left the "game"), what Four Steps.... covers is absolutely critical, I've seen and been in too many startups that failed due to failing in Customer Discovery in one way or another.
- Founders at Work: Stories of Startups' Early Days by Jessica Livingston. [2]
[1] http://www.amazon.com/Four-Steps-Epiphany-Steven-Blank/dp/09...
[2] http://www.amazon.com/Founders-Work-Stories-Startups-Problem...