Getting Started with Raspberry Pi – Mac Rutan – 1+ hour detailed overview of the Pi, with hands-on tutorials

Getting Started with Raspberry Pi – 30 minute overview presentation

Hardware Hacking with Raspberry Pi (Unfinished) – overview of embedded electronics design with Raspberry Pi, especially for those with microcontroller experience

Creating an SD Card for your Raspberry Pi – elinux.org

Raspberry Pi GPIO Reference – elinux.org