Links:

http://gl.ict.usc.edu/Data/HighResProbes/
http://dativ.at/lightprobes/

Length	 34.37 meters[3]
Width	25.61 meters[1]
Height/depth	8.27 meters (including lower cannon and upper sensor array)[8]

Sizes (of the forms, not including armour)
http://www.therpf.com/f10/sw-anh-5-foot-studio-scale-millennium-falcon-build-199048


Way too much detail on the cockpit:
http://www.therpf.com/f11/millennium-falcon-parts-3d-printing-168520/

http://falcon.maruskadesign.com/

Falcon builders' club.
http://studioscale.com/

Calipers on a Master Replica
http://s243.photobucket.com/user/Helder22pictures/library/MR%20Falcon%20bottom

Insane modellers:

http://www.ketzer.com/MF_making_page.html
http://www.m-moeslund.dk/falcon.html (gone)
http://millenniumfalcona.blogspot.co.nz/

Parametrics:
  
    http://www.econym.demon.co.uk/isotut/parametric.htm
    http://www.f-lohmueller.de/pov_tut/all_shapes/shapes570e.htm
  For burns/impacts:
    http://www.f-lohmueller.de/pov_tut/all_shapes/shapes655e.htm

Vince, Geometry For Computer Graphics