Remember, the literature review will be a comprehensive look at your topic. Depending on your topic, you may also review closely related scholarship.
Keep your sources organized! A dissertation or thesis is more like running a marathon than a sprint. Sources you consult today may be critical to your research two years (or more!) from now.
Conducting a lit review requires perseverance in uncovering a comprehensive list of sources, patience in understanding this process is time-consuming, and flexibility in that you undoubtedly will have to use several search strategies and then try them again (that is why it is called research!)
The type of source will determine where you want to search. For example: