I've never been able to find doujinshi on ebay or anywhere else that had siren doujinshi

I think this is one: http://shope.goo.ne.jp/auction/detail/125901960.html

It has a dark cover thats hard to make out the title but the next page has Kanae on it. <3

I want this so bad but I don't know if they would ship outside us or if its an auction or not.

Looks like it is an auction. Even if it doesn't ship to your country you could always use one of those sites that buys something on your behalf. It will cost more but if you want it that badly it will be worth it.

Ooooh, is that a manga based on FS2?

The website says it's a spoof of all of the characters in FS2. Look interesting!