I've just discovered an AMAZING piece of software called UV Layout which makes UV Unwrapping so quick and easy. It's $300 for the Professional version, $200 for the Hobbyist version and $100 for the Student version.
I'm not affiliated with Headus in any way, I just thought I'd let everyone know about it because it's going to save A LOT time messing about doing these things manually.
You can see how quick and easy it is to use by looking at this UV Layout tutorial here:
Yeah, UVLayout is a very cool software. Pretty old too, but still valuable. I have found it specially usefull for organic model unfolds more than for unorganic because the straight lines tend to bend and you have then to play with anchors which adds more work to the equation. You can also check the new Maya Unwrap tools that also count the texel space the UV is utilizing and have some nice measuring tools.