Something like this is usually pretty easy for unwrapping. UV unwrapping is really hard to explain, we were never really taught it in school, and I've never found many good tutorials on it. It's just something you gotta bulldoze through and teach yourself what works and what doesn't.
For most of it I'd probably do a planar UV map for one side, and have the other side a mirror of it directly underneath, so they both share the same UV space (unless you want them to have different textures on each side). Some of it maybe do a cylindrical map, or maybe automatic.
I would convert those nurbs (

) to poly's, then probably a planar map on those.
For the parts that you DO want different textures on both sides, you can select all the faces of one side, do a planar map, then select all the faces of the other side and do another planar map. That way you'll have two sections that you can texture seperately.
Hope this helps!