What are you wanting to do via Bluetooth between your iPad and iPhone ? Bluetooth is aimed at devices such as headphones and keyboards and not, for example, for copying content : supported Bluetooth profiles.
If your phone carrier supports the personal hotspot function (internet tethering on the iPhone 3G) then you should be able to use that to share its internet connection with your iPad and depending on where your contacts are stored get them on the iPad
Personal hotspot : http://support.apple.com/kb/HT4517
Tethering : http://support.apple.com/kb/HT3574