Starting on 01 October, AMC will give us new webisodes leading up to the premiere of season 3 on 14 October. From the USA Today website:
AMC plans to unleash a series of Dead-themed webisodes Oct. 1. Directed by special effects producer Greg Nicotero, the four five-minute eps will feature a new group of characters and be titled Cold Storage. Among the cast members isDaniel Roebuck, who Lost fans may remember as Doc Arzt.
Here's a brief plot description from the network:
Cold Storage tells the story of a young man, Chase (played by Josh Stewart), trying to reach his sister in the early days of the zombie apocalypse. He finds temporary shelter in a storage facility run by a former employee named B.J. (Roebuck); however, things are not what they appear.