Tomte, "Garuda" is not a random title. As you and others have guessed it, Garuda is a mythical bird in Indian mythology just like Phoenix being a mythical bird in Greek mythology. Since the book is about "Demystify Phoenix Internals & Rebuild Phoenix Clone", I have named it as Garuda.

I agree with you, I could have explained the book's content and its title a bit more clearer on my website. I will do it sometime soon.