Okay, I'm not gonna lie, this is one of those rec posts where I picked the theme mostly for self-indulgent purposes. As in, I LOVE Garth (Don't even get me started on my passion for Mr. Fizzles!), but have had a wicked time trying to find where all of the Garth-centric fic in fandom is hiding. Here are a few that I know of--PLEASE make sure you link your favorites in the comments! You'll be doing ALL of us a great service. :)
(You can always start by
checking out the Mr. Fizzles tag on Tumblr. :D)
Mr. Fizzles and Me (Lucifer) by
ryudaaku (PG-13, Garth, Mr. Fizzles, pre-Dean/Castiel, Sam, Lucifer, Gabriel). In which Lucifer is tortured via pop culture, but finds a new vessel; the Winchesters still have to hunt the Leviathan; a certain archangel doesn't stay dead; and Garth and Castiel may have found their best friend. Also, there are hugs.
Three Times the Supernatural Found Garth and One Time He Went Looking for It by
borgmama1of5 (G, Garth)
Exactly what the title says.
Untitled Poem by angelswithphoneboxes (NC-17, Sam/surprise)
Sam gets some loving.
You's a Ho Ho Ho Hot Tub by Anon (NC-17, Garth/Mr. Fizzles)
I'll close with the Mr. Fizzles Appreciation Post... :D