Hello, you can do this:Block a Sender in Gmail
To have Gmail send messages from a specific sender to the Trash automatically:
•Follow the Create a filter link (at the top of any Gmail mailbox, near the search buttons).
•Type the desired email address under From:.
•You can block an entire domain by entering just that. To block all mail from both firstname.lastname@example.org and email@example.com, type "@example.com".
•To block more than one address, separate them with "|" (the vertical bar; typically above the backslash on the keyboard; not including the quotation marks). You can block both firstname.lastname@example.org and email@example.com by typing "firstname.lastname@example.orgemail@example.com", for example.
•Click Next Step ».
•Make sure Delete it is checked under Choose action.
•Click Create Filter.
•Check Also apply filter to __ conversations below to delete previously received messages.
To archive and label instead of delete messages, choose Skip the Inbox (Archive it) and Apply the label: under Choose action when setting up the filter.
The source:http://email.about.com/od/gmailtips/qt/et_block_sender.htm Answered Apr, 19 2011