It's not easy to write research proposals, so look for the topic or idea that you're familiar with, and there should be many books and other resources available on your chosen subject. You may end up with wasted time and frustration if the topic you choose doesn’t support the entire study. Do you have many exciting ideas? Well, they are not important if they don't fit into your research. Don't hesitate to go with other research proposal topics if you have this problem, choose at least a few of them in the beginning, and pick the one supported with a lot of information and academic materials.