How many books are in the Guardians of Series?

The Guardians of the Galaxy series is a comic book series, not a book series. There are hundreds of Guardians of the Galaxy comics, as the characters have been featured in various titles over the years.

However, if you're interested in a specific run of the series, please provide more information, such as:

* Which era of the Guardians are you interested in? (e.g., the original 1969 team, the modern 2008 team, etc.)

* Which publisher are you looking at? (e.g., Marvel Comics, Dark Horse Comics, etc.)

With more context, I can give you a more specific answer.