Freebbble!

This looks really cool. Includes the iMac, iPhone 5S, Iphone 5C, Macbook Pro/Air, iPad and iPad Mini wireframes.

Apple Product Line Wireframe PSD is a free Mockup design resource made by Dribbble user Rubayath. As far as I can tell, its license is Free for Commercial and Personal Purposes.

Helpful hint: Dribbble users are nice. If the license is unknown, it is usually because they forgot to mention it explicitly; not because they were being stingy. Ask nicely and they will probably allow you to use it.