Thanks for your encouragements!
You can use the part library (View - Library Browser) to insert symbols as blocks into a QCAD drawing.
The part library browser supports files of type DXF, DWG (QCAD Pro only) or SVG (subset supported).
Additional symbols are available at:http://qcad.org/en/qcad-add-ons
The package called 'thenounproject.com' might contain some symbols that might be useful for you. You can also browse their icons online at thenounproject.com.