The Garfield comic book, published by Boom! Studios imprint KaBOOM!, has been in print since May 2012. The series is generally written by Mark Evanier and illustrated by Gary Barker.
Pet Force has a sub-line in the series.
In January 2015, a 4-part comic book based on Garfield: His 9 Lives began to be released.
A Christmas special entitled "Garfield's Cheesy Holiday Special #1" was released in December 2015. 
"Garfield 2016 Summer Special #1" was released on July 27th, 2016. 
"Garfield's Big Fat Hairy Adventure", the first original graphic novel for Garfield, was released on October 25th, 2016. 
Pet Force Specials
Garfield: Pet Force Special #1
Garfield: Pet Force 2014 Special
Garfield's Cheesy Holiday Special #1
Garfield 2016 Summer Special #1
Garfield's Big Fat Hairy Adventure