GTA2 MP will stay here forever.
Thank you for being interested in this.
http://gtamp.com/gta2/- here is everything (in english) you need to know to start playing this wonderful game.
EDIT: i didn't see the pinned topic that contain this mod, sorry, anyone would link me the game
I didn't see it either.
The main reason that GTA2 MP is not so popular is that you need to have your ports forwarded and it can't be done automatically.
If R* would release the code, GTA2 would be still being played by many people around the world cause usually they are disgusted if they have to forward the ports by themselves, which is double saddening cause when you see these movies made by players it looks like a great fun - believe me it is if you forward your ports (which is not that hard).
If you need any assistance, we have a great support on GH, just ask here or on GH - personally I will do my best to make sure you can start - through all these years I've been there, it started to become important for me to gain some players in the community.
Also there are specific periods when there are more/less players so stay calm if there is no people on GH because players come in waves (usually on weekends).