Below is a link to a Galaxy class mesh in LW format by Ralph Schoberth, with a link to an image gallery. Failing that, you could always do a conversion (with the authors permission) of the 3DS Max Galaxy class ship at startrekaustralia.com.
Andy.
http://privat.schlund.de/S/SchoberthRalph/1701d.htm
http://privat.schlund.de/S/SchoberthRalph/trek1.htm
