I've updated my e-book to include additional photos for one of the Messina tailors, a few minor typographic corrections and more information on shopping and restaurants. The link above also quotes or references a couple of reviews of the guide by author Bruce Boyer and Hugo Jacomet of Parisian Gentleman.
I also provide further editorial commentary and information on one of the cities in particular, Messina. There, within a three block radius, you'll find a fully stocked fabric shop featuring well-known Italian cloths such as Drapers, Vitale Barberis Canonico, Cacciapoli and others, as well as a trimmings/linings shop and a button shop. Once you add a few tailors located nearby, all you need to do is mix and stir and you're all set for a complete tailoring experience. All within a few minutes walking distance of each other.
This miniature, walkable ecosystem of tailors and suppliers used to be commonplace in small towns and cities across Italy but now is very rare. It's actually difficult to find this configuration anywhere else in the world (in the West especially) with the exception of Savile Row. Mentioning Messina and Savile Row in the same breath is certainly not something I would have imagined before I had written this e-book.
I'm also looking into making available a print version of the guide (likely through a print-on-demand service) in the near future.