1st Real Affiliate Sale!
The only affiliate earnings I've had were from building an incentive site that brought me about $50 or so.
Most of my money is earned from freelance programming, which is good for seed money but not good if you want to earn more than a few thousand each month.
Anyway, I recently bought a WSO that helped me decide how to build my business. Until then, I would get an idea, try to start it out, then clean house a little and try to focus on 2 or 3 things instead of the 5+. Every few months this would happen again. Well, I can't say that I have stopped doing this entirely, but I have successfully been able to focus on one site and start earning from it.
I did it almost exactly like everybody says, which is the real kicker. This stuff has been said over and over for free through this forum, and in multiple WSO's. Build a site that people will be interested in, add content on a regular basis, and add relevant affiliate products in there when you can. My site's been online for a little over a month, and hasn't really earned much. I have one adsense block that has earned me about $4 for only 6 clicks. I get about 10 - 20 unique hits per weekday, and 5 - 10 on the weekend days. 90% of my hits are from the Search Engines, with all kinds of different keyword searches. Overall, not bad for being online for a month. I've done some backlinking, but I'm still only at a PR0.
This isn't anything to brag about, but things finally turned around when I noticed a $45 commission in my CJ account today. This was from just one product, too. I was a little disappointed that the clickbank product I've been promoting hasn't sold yet, but this is just as good.

What have I learned so far?
-Focus, focus, focus. Stick with one or two sites and get them earning. It's much easier to spend your time on one site, then to spend your time on several sites.
-Adsense is nice to give you a good feeling about your site, but the real money is earned through affiliate programs.
-Social Bookmarking can provide a lot of traffic in a short time, but not everybody (including me) will be able to properly monetize on that traffic. I think you should focus more on getting the backlinks from social bookmarking, rather than the traffic.
I'm tired of my signature... Deleted.