HeinOnline is one of our favorite databases. In fact, we're teaching a CLE class on how to get the most out of HeinOnline next week! If you can't make our class (Wednesday, May 20th, noon-1 p.m.) you can still learn a lot about HeinOnline from their support site http://help.heinonline.org/.
Read FAQs and get library-specific support (with overviews of special search fields and shortcuts). An extensive webinar and online training video archive is also available.