I've made quite a number of drawings using XFIG over the years that are viewable on Coprolite.com, NetAdminTools.com, and SolarPower.org. I have collected the components in these drawings so that you may use them in your XFIG Libraries directory if you wish.
Here is a graphic of all of components in the library. The individual files are below, as well as a tarball that you can extract in your Libraries directory.