1. Comic Monsters
This is a huge blog and news site for monster-themed comic books. There's a community area, reviews, info on horror comic toys, features on various artists, and some free horror comics.
2. Everyday Decay
A webcomic about zombies. It's really well done! Recommended. He hasn't posted any new comics in a while, but you'll enjoy what's already there.
3. Lovecraft is Missing
An online webcomic about H.P. Lovecraft, updated once a week. There will be 144 pages total before the story is finished.
4. Spookyland - Lenore
I doubt I need to tell you anything more about the ubercool little dead girl.
5. Making Fiends
Two series worth of online webisodes, starring Vendetta (who makes fiends) and Charlotte (who makes friends). Very fun to watch!
6. Precious Miseries
This comic follows the lives of orphans living in Precious Miseries Manor. The orphans themselves are punks, goths and Lolitas. Click here to read the online comic. There's a silly sprites adoptions page if you like that sort of thing. (I sort of do!)
7. Dead in Dreamland
A manga-style comic. A departure from what I usually link to, but I find it refreshing.
A comic by Bloodfire Studios.
Check this out really quickly - it's a Norwegian black-metal (meaning not goth) comic strip featured in a UK newspaper.
10. Putrid Pal
A cute webcomic about an undead little French boy. A vinyl toy has been made of the main character.
11. The Zombie Hunters
12. We Kill Monsters
Two brothers discover that monsters are real and have begun to infest the world. Not a web comic - I usually only link to comics you can read online. But just this once.. because this is cool!
13. Biff the Vampire
A silly comic. I love that they aren't afraid to be goofy. The main character is Biff Strigoi Morti.