Someone asked me a good question the other day, concerning the various websites and tools that I find and report on regularly. "Where do you find all these sites?" It's a valid question for sure and the answer is not some trade secret that I want to take to my grave. There isn't a single clear answer (but there are several not so clear ones!!!)
One of the primary sources for new sites worth investigating is KillerStartups, a fantastic site dedicated to highlighting interesting Internet ventures of all kind. They promote 15 new sites a day and keep an excellent archive of their daily posts, as well as a top ten list that is worth exploring in detail. That's one of the answers; the other part of the answer is good search techniques and the final part of the answer is taking notes. Lots and lots of notes. Every little bit of information, URLs and images is usually captured using Evernote (and in some cases, when I am away from my computer or when it's faster, I also use GeniusScan!!!).
Of course, it really helps to read a lot. But that's just a question of practice for most people. As a final clarification, let me point out that I browse the Internet an average of 1 to 2 hours over the course of a day (it does help that I work in a computer-related field though) and don't watch television. It's amazing how much time you liberate if you drop the boob-tube! Try it sometimes!