Now even though I happened to see the book on IndyPlanet, I would avoid buying it from them unless you plan to do so in digital format. The shipping costs from print books are simply brutal.
When I pointed this out on Twitter recently, writer Michael McAdam offered to ship the books to me if I bought directly from him. There's still a cost involved, of course, but it is reduced significantly.
I doubt McAdam offered this to me because I'm particularly awesome (though it's entirely possible). I'm sure the offer applies to any potential customer. So if you decide to get your hands on individual issues of Thunder, go straight to the source or contact McAdam through the Two Gargoyles Twitter account.
And coincidentally, as I was confirming Two Gargoyles Twitter account name, McAdam happened to post a picture of a new promotional poster for Thunder. Have a look below, and Mike, if/when you read this, remind me to add one to my order when I get Thunder #6 from you some day.