There is no manual that comes with the iPad 2. Apple assumes that their product is so easy to use that no manual is necessary. They figured that no one would read it anyways.
There is however a card that tells you where the On/Off/Sleep/Wake button is. And the back of the card tells you how to sync your iPad.
But if you are one of those who like to read manuals, you can find the iPad manuals online by …
a) going to Apple.com website
b) click on “Support” on the top menu
c) click on “iPad” on the left menu
d) and then click “Manuals”
e) Now you can select the manual that you are interested in.
The iPad 2 User Guide for operating system version iOS 4.3 is located here …
And the original iPad User Guide for operating system version iOS 3.2 is located here …
If you like, you can even read the User Guide on your iPad by using Safari and navigating to the web address. This is assuming that you had figured out how to connect your iPad to the Internet. If not, you can simply read the manual on your computer via your browser.
Another option is that, if you have iBooks installed, then you can download and read these free ebooks: iPad User Guide for iOS 4.3 and iPad 2 Starter Guide (iBooks > Store > Top Charts).