Hmmm... It took quite a few years to build up decent traffic. At first I just asked friends to submit some questions (like http://isitnormal.com/story/-1/) and I seeded some myself. I posted the link on various forums and submitted it to "cool site of the day" type stuff. The concept has always resonated with people and I managed to get a few semi-decent sites to link to it early on.

New content started to slowly trickle in. Eventually search engines found the existing content. That search traffic led to more submissions. Rinse, repeat.

Most of the traffic comes from search now. Apparently people search for "is it normal that I ____" or "is it normal to ____" a lot. I didn't really anticipate this when I started the site in late 2004, but I guess I got a bit lucky with the name in that regard. However, if I had to do it all over again I'd probably pick a subject matter that's easier to monetize. iPods and cars instead of fetishes and phobias.