Most software has a "help" menu that can answer many of your questions and help you figure out how to do things. You can also search the internet for help sites, user forums, and tutorials.
I've also found that most colleges have great resources, tutorials, and how-to's about software.
Excellent tutorial on using Excel for Physics labs (graphs and formulas)
(graphic downloaded 9-25-09 from http://acda.org/formregistry )