Hey looks good. Decent site for blueprints in general is http://www.the-blueprints.com
you need to sign up but its free and they have loads of well everything lol.
Back to your project tho. Your headphones look to be all one piece which if you look at most is not actually the case... This will also make it really difficult to texture later on. So i would suggest making each part an individual piece e.g. have the pads at 1 object, the wire as another, the head rest as another and so on.
I love the idea of the copper / steampunk headphones thing. I think it would work really well but the nature vines stuff sounds really fun to work on too (even tho i hate doing organic things! lol)
- Big Tom