If you're still stuck on choosing a topic or developing a broad topic into something manageable for your project, get help from a professional! The consultants atthe University Writing Centerare waiting to assist you with any part of the writing process.
Another important reason to do background research is that you can gain a sense of the vocabulary of your topic. Identifying those important keywords, phrases, concepts, etc. that are specific to your topic will allow you to find the most relevant sources whether you're searching online or in the library. Performing one or two searches likely won't give you everything you need.
Watch this short video for more on keywords. Note: this video is specific to searching in a university library, which this guide goes into detail on on the Library Research Tools page.
Wikipedia is rarely an acceptable source to cite in a research paper. However, it can be a great source for background information about research topics and a source for some of the research already done on certain topics.