If you have iTunes 9.2 and iOS 4 installed on your iPad, iPhone, or iPod touch, iBooks can view PDF files. There’s a simple way to get those PDFs into iTunes for syncing to your iOS device.
All you have to do is create an alias of iTunes.app and drag it to youruserfolder/Library/PDF Services. (Create the folder if it doesn’t already exist.) If you wish, rename the alias something like Add to iTunes as PDF.
That done, the next time you’re viewing a document you’d like to read later on your iOS 4 device, choose File > Print, click the PDF button on the bottom-left corner of the dialog box, and choose iTunes from the list. (Bonus tip: To make the PDF more readable, turn on Safari 5’s Reader function before printing.) The iTunes app will launch and receive the PDF. Next time you sync your device, the document will be synced as well.