“How do I block someone on Google Talk from Gmail?”
1. Log into your Gmail account.
2. On the left hand side find the “Chat” box and click on the little square to expand the box to view your Gmail Chat contacts.
3. Find the contact you want to block on Gmail Talk. Mouse over the contact to view options.
4. Click “More” to view a list of options from a drop down menu.
5. Now just click “Block” to finish the job.