If you are using a computer that isn’t running iTunes, or if your iPad isn’t associated with iTunes on that computer, you can still get your files onto your iPad using Dropbox. You can import PDF files into iBooks, Word documents into Pages, Excel spreadsheets into Numbers, etc.
1. On your computer, drag (or copy) the desired files into your My Dropbox folder.
2. Go to your iPad and launch the Dropbox application.
3. Go to the upper-left corner and select the Dropbox icon.
4. Select the desired file that you want to import.
5. When the file has finished loading, select the Open In icon in the upper-right corner.
6. Select the desired application that you want to open the file in (iBooks for .pdf, Pages for .doc, Numbers for .xls, etc.)
Your file will be imported onto your iPad, and without having to use iTunes.