It sounds like you're most interested in playing SNES games online. Although Snes9x does have netplay support, the current state of the feature is not yet well-programmed and thus rather impractical for use outside of a private LAN. There are not yet any decent SNES emulators that directly support Kaillera, but ZSNES's own netplay support is just as good if not better, and it can run smoothly through even a 56k connection. Look into downloading zbattle at
http://www.zbattle.net/
I'm not sure if there is any comprehensive list of Kaillera-supported emulators, but to name a few: WinUAE, Jnes, NESten, NNNesterJ, Gens, Project64k, 1964, MAME32k, MAMElang32, [Neo] Mame32 Kaillera, ePSXe Cyberpad, Nebula, and Final Burn Alpha. There are also many other emulators that implement their own non-standard netplay protocols such as RockNES, Nestopia, FCE Ultra, Snes9x, and ZSNES.
-hanzou