"For a limited time, Skybound is teaming up with Humble Bundle to offer the first three issues of The Walking Dead absolutely free. Start your comic collection off the right way, with one of today's hottest titles."
Not sure when it ends.
Whoops you're right, its definitely mentioned as a footnote in that post. To be fair though most people would miss out since the title doesn't suggest there are any free issues.
D'oh - thought it was the Telltale game.
These bundles are awesome. I've ponied up the $15 for three of the comic bundles, although only read 1/2 of the first one so far. Even at $15 they are a bargain.
Pretty sure this was mentioned in the HB Walking Dead post here
Also for as little as 1c you can get the first volume of Walking Dead (issue 1-6) and three other 1st volumes of other comics