Check out the new IES lighting, if you get a chance. That is real world photometric data, incorporated into a 3d light source :)
Here are links to a bunch free IES files:
http://www.colorkinetics.com/support/ies/
http://www.cooperlighting.com/content/design/etools.cfm
http://www.erco.com/news/en/en_frameset_news.htm
http://genet.gelighting.com/LightProducts/Dispatcher?REQUEST=IESCATEGORYPAGE
http://www.lithonia.com/Search.asp#Photometric
http://www.lumec.com/documents/photometrie.html
http://www.nam.lighting.philips.com/us/ecatalog/photometric.php?mode=1
http://www.sternerlighting.com/PhtmtrcDB/PhtmIndex.html

Friends don't let friends use booleans.