For those who are interested in researching for their own betterment or looking to get as much information as possible from various sources, look into the following links!
For some basic knowledge of what you need to do to file taxes, the TurboTax website is a great resource to get in the mind of an individual sending their forms in to the IRS. USA.gov provides similar information from a less company-oriented approach, while the IRS's website gives out filing information for individuals, companies, charities, and international taxpayers. These sources are great options for learning the basic processes of filing and what it takes to do so.
IRS Filing Information
In terms of finding some discounted hard copies of casebooks and treatises to learn about tax law from education companies, the best website for purchasing these used items is AbeBooks. This resource is a great place to pick up some vaguely older editions of treatises and textbooks--or new editions for all in-demand books--and will likely be a cheaper way to learn about topics in a self-guided fashion.
In the realm of self-guided learning, Quimbee has an excellent course offering on federal income tax, and CALI offers almost 500 income tax quiz-oriented learning modules to grasp basic and complex ideas surrounding tax law.
Quimbee Study Aid