Storm, I don't think that there are many people who can teach you this. It's all about experience and not so much about a ready-made tutorial. I mean, trying to copy the idea is one thing, but starting from scratch... well that asks for a lot of talent
If it was done in PS, trust me, then it would take more than just one book page to explain all the steps.
You have to know the restrictions of Photoshop and yes and even if it's possible in Photoshop, the question will be; is it worth all the efforts? Or should you just focus on 3D instead?
Yes, when you finish something like this you've learned a few techniques and more about Photoshop, but does it teach you a lot about creativity?
See, personally I rather spend my time on 10 smaller challenges, instead of spending the same time on how to create a 3D cell-phone; it teaches you techniques, but not art. I know, some people won't agree with me, but that's ok; we all have different ideas about this subject.
I do wish you all the luck to find someone who can help you with this