Beginners guide to PPC assembly

Now with more and more devices using some form of PowerPC processor its becoming more apparent to me that at some point I'm going to have to learn Assembly for the PPC. Luckily IBM has a nice little introduction into assembler for the PPC, but isn't a fully blown tutorial basically it acts as a good place to start. Think of it as the first few chapters of just about any generic programming book out there. In any case I found it helpful, so I figure it might help you too. Check it out here.