Did this in 2007 and I was looking at that thread and none of those who played are still on dis (or have changed their names).
So if you want an online game of speedball 2 download this:
Th folder contains the gens megadrive emulator with kalleira onlinegaming client and a rom for speedball II.
Once you log onto kalleira you choose a server. post the server and someon can join you and play.