11 Resources for Learning Unix Programming:
I tend to steer clear of the thick reference books and go instead for books that give me a look into how smart people think about programming.
I have a soft spot in my heart for books that are way too long. But Jesse’s on to something, I think. The problem with big Unix books is that they are tomes of arcane rites; most of it just isn’t relevant to those building systems on a modern Unix (Linux) with modern tools (Java, Python, Ruby, etc.).
Jesse’s way of learning you a Unix is way better, honestly. Read concise programs, cross-reference them with manual pages. Try writing your own stuff. Rinse. Repeat.
Adam Keys is typing 
I’m glad you agree :)
Unfortunately I don’t think we’ve convinced the publishers yet. On that note the best sources I’ve found for this kind of stuff is old writings from early Unix folk. If you can find decades old articles from the likes of Pike, Ritchie, Kernighan, McIlroy, et al. it will certainly be worth a read.
For example, here’s Rob Pike’s notes on C programming style: http://doc.cat-v.org/bell_labs/pikestyle. I’m not a C programmer but there’s much wisdom packed into those notes for a programmer of any language.