Looks like those other two tutorials that the EvilWalrus promised are posted - one's a cool one on a MySQL error function and the other is a good intro tutorial to show you how to connect to a MySQL database. Read on!
Now, I know this article's a bit old, but I just found it and thought it was a really cool idea. For those out there that use the AvantGo service, you know what this is all about - there is an article over on the WebMonkey that talks about creating AvantGo images with PHP. These aren't your standard GIF or JPEG images either. Since there are so many different standards as to graphics on PDAs right now, they suggest using PHP to discern between the different handhelds and then making it from there. Pretty cool stuff, be sure to give it a read.