The quality of the material relating to a given subject is usually greatly enhanced if you set as your goal the identification of a full range of source material. Everything on a topic is rarely found in books alone. Newspaper articles lend an immediacy to a topic while magazines articles on the same event might include more background information. A book may be more reflective in its treatment of the subject and a person who testifies about the same event may add a perspective that a print document may not reflect.
The library at UCLA has an interesting tutorial that considers how time is a factor in the use of a range of sources.
Looking for information on colonial America may suggest to some that dusty shelves of long unopened books stashed away by historians will reap the most useful details but that's not necessarily the case. Some material may be found stashed away but quite a bit is all around us. Take a look at the range of sources on the final pathfinder and consider what tools and avenues might lead to those findings. How would you find and utilize videos, historical societies, people, museums, etc. to add dimension and scope to your research?
Another intricate part of research that improves with practice is sorting through all that is found. It's not the amount of information you find but the items you select from the morass. Along related lines you'll also be expected to evaluate the quality of your sources and to be able to articulate their relevance to the task at hand. Click here to go to the Evaluating and Sorting file.