This probably wouldn't be quick, however if you're interested in modelling traffic paraphernalia to detail out your scene I've found most D.O.T. sites have a raft of standard details in CAD format for gantries, crash barriers, lamps etc.
http://www.dot.state.tx.us/business/standardplanfiles.htm
Example: ftp://ftp.dot.state.tx.us/pub/txdot-info/cmd/cserve/standard/traffic/stds66.pdf
L