I recently posted an article on the General Chat board asking if anyone was here was on GGPO. For a little extra info here's the link: http://segahub.org/index.php?topic=5303.0
retro_killa was interested, and so he asked me to write a tutorial. Sounded like a plan to me, so let's get it going.
Here's the ROM compatibility list (as of 15 Feb 2010)
Dungeons and Dragons Shadow Over Mystara
Fatal Fury Special
Garou: Mark of the Wolves
Hyper Street Fighter 2: The Anniversary Edition
JoJo's Bizarre Adventure
King of Fighters 2000
King of Fighters 2002
King of Fighters 97
King of Fighters 98
Last Blade 2
Marvel Super Heroes
Marvel Super Heroes vs. Street Fighter
Marvel vs. Capcom
Metal Slug X - Super Vehicle-001
Night Warriors: Darkstalkers' Revenge
Samurai Shodown 2
Street Fighter Alpha 1, 2, 2 Gold and 3
Street Fighter 2 Koryu, Champion Edition and Hyper Edition
Street Fighter 3: 3rd Strike
Super Puzzle Fighter 2 Turbo
Super Street Fighter 2 Turbo
X-Men Children of the Atom
X-Men vs. Street Fighter
1. Hit up http://ggpo.net/
and go to the Downloads page. Download everything it says you should download.
2. Install everything. I'm pretty sure this doesn't require screenshots.
3. Place the roms that you own into the rom folder in the GGPO folder.
*note* To play NeoGeo roms, you need the NeoGeo BIOS rom. For Street Figher Alpha 3, you need to download a savestate. There's a link in the SFA3 room description. For Street Fighter 3: 3rd Strike, you need sfiii3.zip AND sfiii3n.zip.
4. Launch GGPO. You'll be welcomed with a login screen.
6. After registering, you'll receive a confirmation email from the higher-ups. Validate yourself, and you're ready to go. So, now log into GGPO. You'll start off in the room known as The Lobby.
7. Pick your game. You now have two options:
7a) Challenge someone, or
7b) Wait until someone challenges you.
Sorry for the absence of a screenshot here - sometimes it's hard to get a game. I'll upload a screenie here as soon as I get the chance.
Now you can play awesome arcade classics online! Meet me on there, the name's IsshunSengeki, I'm usually in the SFA3 room, the Garou room or the SF3 room. See you guys there!