I want to make my foz faster, louder, and all around nastier but I'm having trouble rinding parts intended for the S and not just the Xt. If you have any information i would really appreciate a nudge in the right direction. :)

What year is yours mate? Basically 90% of the impreza form the same year should go on

It's a 2006. What can I do to it to make it faster without requiring a dyno?

Normally asperated I take it ? Apart from weight reduction. I'd go handling so alloy droplinks to replace the crappy subaru ones maybe a thicker rear anti roll bar, should make turn in better and reduce understeer.

Think yours will have equal length headers so you won't get the boxer sound unfortunately

It sounds alright. I guess if you do anything with exhaust (down pipe,header,ect.) it requires a dyno. Please correct me if I'm mistaken.

Not sure on a n/a car as the main reason for remap on decatting is to stop overboost and what not, not sure where & how many lambda sensors yours have, removing the lower one on newer models with throw up an engine managment light which requires mapping out. Could always go sports cat system should have the relevant bungs for sensors.

Have any good suggestions on where to get them?

Not sure as I've never looked at getting stuff for the newer foz,there seems to be quite a lot available from the states, as for exhausts you'd need to check the layout of the headers and downpipe length to see if any impreza parts fit