The Ultimate Guide to Making Money

Don't be put off by the title. Ramit has some truly good advice on this subject (among others), which I and hundreds of thousands of people have used successfully. It's not about penny-punching, but about negotiating a higher salary (how to do it), establishing multiple streams of income, charging more for what you already love to do, etc. Highly recommend reading this all the way through. It's completely free, to boot.