Here is where you can find Mathematica on the Haverford campus.
Here are some instructions on how to download a copy of Mathematica to your computer (only if connected to the Haverford College network!).
Here is a tutorial notebook that helps you get accustomed to Mathematica; download it to your computer and open it with Mathematica.
Notebooks and palettes by Steven Amgott:
Visit Steve Amgott's Swarthmore Mathematica Stuff pages.
Exploring Abstract Algebra with Mathematica:
Mathematica packages and sample labs for use with Abstract Algebra courses are available at http://www.central.edu/eaam.html.
At Wolfram.com: (creators of Mathematica)
http://library.wolfram.com/tutorials (Various tutorial written by the "Mathematica people")
http://www.wolfram.com/ (Wolfram Research's home page)
http://support.wolfram.com/ (technical support FAQs - note that only contact people can link to most of the rest of the support site)