There's a lot of money to be made at small stakes no-limit hold'em because. surprise, surprise. most of the players aren't very good. However, few players understand exactly how to exploit these games. Competent players who generally play larger stakes will, of course, beat them. But they won't beat them for nearly as much as they ought to. Why? Because they don't understand how to adjust correctly. Playing a solid, competent, decently aggressive style is a strategy that will be profitable.
That said, you should not be content with just beating these games -- you should be absolutely crushing them. The trick to doing this is to disregard a lot of 'correct' poker and get way out of line at the right times. The methods required are far from obvious or intuitive, but in Mastering Small Stakes No-Limit Hold'em, Jonathan Little explains them in great detail. Here, Little constructs a basic strategy to crush small stakes games and also identifies the adjustments that need to be made when facing more competent opposition. Jonathan Little is a professional poker player who has cashed over $6,400,000 playing tournament poker over the last 10 years. He also plays high stake cash games on a regular basis. He is the author of 11 best-selling poker books and he owns and operates the poker training site, PokerCoaching.com.
He also runs JonathanLittlePoker.com.