VideoTrace (beta for the last few years) http://punchcard.com.au/ Great for getting a rough base mesh to work with (same procedure as http://www.thomasbaron.net/2011/05/modeling-without-blueprints-from-pictures/ but much easier to work with than insight3d)
Xray unwrap 1.5 will be available soon by the way. This update will be included in the unwrap modifier, and add powerful tools like auto uv packing and rescaling (according to texel-ratio), according to the demo video. http://www.raylightgames.com/2010/05/sneakpeek-xrayunwrap-15-rc1/