How can writers effectively research material for their writing projects without becoming overwhelmed?

Our minds are sponges. Relying on some of the information that you've come across is a great way to begin your writing efforts. You can then bolster your writing with your research. If you want to go the thesis-style route, then you're going to want to compile a list of your references before you get started with your writing. I tend to like this approach because it takes the pressure off trying to find sources along the way. That said, don't be afraid of looking for new sources if you've already compiled a list!