So recently I've downloaded the Community Ded. Server download because I want to give server hosting a try (with 30Mbps down speed and about 2-3Mbps up, why not?). The included instructions that came with the download says I need a gamespy account to continue with the setup process.

Here's where I got confused; can I use a Gamespy account that I use for Crysis 1 online in this scenario, where I have to setup a server?

here you go.Follow this steps.You need to ame another crysis2 account with different email ID.
http://www.gamesas.com/forums/viewtopic.php?f=40&t=35476&start=0