The 2011 NEC is almost 900 pages long, in three-ring binder form. The good news is that compliance is far easier than the size of the NEC might suggest.
Table 90.3 shows this graphically. The first four chapters apply generally to all installations, and Chapter One is so short it contains only two Articles. Chapters 5, 6, and 7 are the "special" chapters. The requirements pertain to special occupancies, equipment, and conditions, respectively. Chapter 8, which is short, pertains to communications systems. Chapter 9 contains useful tables, and the Annexes contain useful examples and information. With this framework in mind, you can quickly identify where to find the appropriate Code requirements.
For example, say you're installing a transformer and panel to power lighting in a new building. Article 110 is always going to apply, so you begin there. What about Chapter 2 requirements? Look in the table of contents, and you see Art. 220 (branch circuits), Art. 240 (overcurrent protection), and Art. 250, Part V (bonding) apply. You can take a similar approach with Chapters 3 and 4. Since this isn't a "special" installation, you can ignore Chapters 5, 6, and 7.