EXCELLENT point Lisa! I see so many affiliates doing the same thing you did. In fact I just remembered that the 1st affiliate programs I promoted about 8 years ago before I had a CLUE, were hosting and merchant accounts.
Another point besides getting lost in the sea of other Internet marketers is that webmasters can be a tough crowd to sell to.
I always recommend affiliate start with something they know about and are passionate about - hopefully in a niche. It can make generating content easier. Especially important, if you promote something you are passionate about it can keep you motivated in the early days when there is no money coming in.
Another great lesson learned!
Who's next???