You can start by typing in AEHELP at the command line and going through the tutorials. After that you can buy the Ascent Electrical Fundamentals (www.ascented.com) or take a class from a local reseller. Just make sure you don't use the Autodesk books. They read like Japanese VCR instructions.
We also have online classes available through Cloud based systems with a live instructor if you prefer. But that definitely costs more than self learning.