The U.S. Census Bureau provides a wealth of online training materials, courses, and single session webinars. Check out their workshop site to find past webinars by topic. Webinars are free to anyone, thought most will require advance registration, and some are intended for members of the news media prior to a big release of new data.
See researchdata.berkeley.edu for more information.
Need help with research? Have a question about the collection or the UC Berkeley Library? Here are two ways to get in touch with me: