Hi,
You can check the Hosts file before running off to the Apple Store.
Make the finder the front app (listed in the Menu Bar)
If a Finder window is not open use the option in the File Menu.
Then go to the View Menu > Customise Toolbar.
Drag the QuickLook eye type icon to the Toolbar.

Close the Customise slide (Done Button)
Close the Finder Window
In the Go Menu > Go to Folder type /etc/Hosts in the dialogue box that appears.
This will go to the etc folder and highlight the Hosts file
Now click the QuickLook button in the finder window's Toolbar
It will offer a way to Open It (TextEdit)
Use this and it should look like this if it has not been changed

If QuckLook does not offer the TextEdit Option close the QuickLook slide
Right Click the Host File and use the Open With option to select TextEdit.
Using Terminal is only one way to Edit this file if needed.

10:26 PM Thursday; February 21, 2013
Please, if posting Logs, do not post any Log info after the line "Binary Images for iChat"
iMac 2.5Ghz 5i 2011 (Mountain Lion 10.8.2)
G4/1GhzDual MDD (Leopard 10.5.8)
MacBookPro 2Gb (Snow Leopard 10.6.8)
Mac OS X (10.6.8),
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"Limit the Logs to the Bits above Binary Images." No, Seriously