Just for the holidays, from now until Wednesday, December 28th, the Kindle version of The Guide to Classic Graphic Adventures will be 50% off. That means $4.99 for US buyers, and assorted similar discounts for other regions based on whatever conversion metric Amazon is using at the moment. This is only going for a week, so it's a good time to pick it up, especially if you get a Kindle this holiday season!
Additionally, the book is also enrolled in the Amazon KDP Select program. This means that if you have a Kindle and Amazon Prime, you can borrow the book, for free, although you're limited to one title a month. Keep in mind though that when they mean "Kindle" they mean "an official Kindle device". I only own mobile decides that run Kindle software, and this doesn't apply if you're using an iPhone, Android or the PC reading software. I made the mistake of purchasing my own book to test it out, and based on the refund numbers, it seems like at least one other person did too. Sorry! It's a neat program although initially a little vague.
Finally, the book has always been available in America, the United Kingdom and Germany, but Amazon has expanded its Kindle store to include Italy, France and Spain, so do check that out as well.