I would analyze those sites using knowledge you have so far. Experiment, changing a few things. If that doesn't work, put the sites aside and start another. It could be too broad a niche, traffic that's not directed, not geared to buying because you haven't used buying keywords, or it could be where you put things in your site. Your copy on the squeeze page may not be leading to a sale. In other words, it could be anything. Common mistake and one I've made is too broad a niche. Maybe you need to narrow your niche. Just food for thought. Don't worry about it though. It'll work out. This is the learning process.