Know thy e-mail id

You can also visit his/her profile page and get the id
Gtalk lets you know the email id any orkut member if you are his /her orkut buddy

What if you are not his/her buddy

• Open the profile of the Orkut member whose e-mail address you want to know.
• Click on "ignore user" option .
• Now sign in to your Gtalk messenger.
• Click on "settings" & choose blocked tab.

VOLLA! The e-mail address of the blocked Orkut member is visible.

Now you can unblock him by visiting the "list" option on your profile page

Install Gtalk (from Googlepack)