Any joystick interface will work with any sim that accepts joysticks. This includes most of the full-size or RC sims e.g. FMS which is free.
A suitable interface is available from
http://www.rc-electronics.co.uk/ (for under $50, even the USB version). There are plenty of others around.
BTW the Ripmax interface suggested by tiggerinva does not work with Win XP.
Steve