The first tip for finding a perfect topic is to choose something that you want to learn more about and spend time researching. Make a list of every possible idea that comes to mind. Move through the list rather quickly, so you really go with your gut feeling. If you do not care much about the topic, then you should immediately cross it off of your list.
Browse the Internet for Inspiration
If you cannot brainstorm a topic on your own, you can search the Internet for a topics. There are plenty of places that can be used to find inspirations for topics. Most advanced degrees have professional organizations and many of those organizations will have links that you can use for your hunt for a topic. Online journals can also be good sources for ideas. You can also look at online wikis in your degree. First begin looking at broad topics. Once you narrow down the broad topics, you should then look for topics that you can spend time with without getting bored. You should also take a look at what research is available, because without research, your topic will go nowhere fast. Writing a dissertation takes about one year to complete. Some people take more than three or four years, simply because their topics are so complicated.
Search the Dissertation Database
Another useful place to hunt for a topic is through the dissertation database. Many colleges and universities have databases that are full of dissertations in a wide variety of topics. If you search for general topics, you will quickly be able to find dissertations that have covered those topics. Then, you can see what people have researched. You will be able to cross of ideas and add to your list with ideas that have inspired you. Even if you take longer than you expect to find a topic, you should try to enjoy the journey on your way to finding a dissertation topic.