If it's this one you're using,
http://gear.ign.com/articles/562/562988p1.htmlThen it's JUST like the one I use, only different colors! Saitek X-45. Look up that one and see how similar they are! You may be able to download drivers for that stick from Saitek. Outside, they are SOOO close, that I bet a lot (if not most or all) of the internals are also the same. Is it USB?
I'm suprised that windows didn't automatically do it for you? It did for me, and lovin this thing on Win 7 64 bit!

Hope this helps...
****EDIT****
This came from that same page, but IDK how old this info is.
"As the Flight Stick 2 is a USB device, in theory it could be used with multiple devices, especially a PC. Unfortunately, we were unable to find a way to make it work, though we sent notice off to Hori for help. Hori's response is as follows:
The Hori Flightstick 2 was designed specifically with Ace Combat 5 for the PS2 in mind. However, since it has a USB port, theoretically, it is PC compatible/can work with other computer games. Namco only supports the usage of the Hori Flightstick 2 to provide the optimal aerial combat experience with AC5.
So, in theory, it could work on a PC, it just doesn't right now (or at least we haven't figured it out). As the Flight Stick 2 is basically identical to the Saitek X45, we tried installing the drivers for that device, but to no avail; Saitek's drivers needed to detect a Saitek joystick before installation, so that didn't help much."
Maybe there is now a "cheat" or a "work around".
Hope this helps...
Da End