hi i have a 2007 wrx hatch and i was the same when looking for parts for my build,everything says 2008,well your ok to get 2008/9 wrx parts as they will fit,rear spoiler is tiny i changed mine to a sti spoiler just the same fittings,if you buy a front splitter just make sure its for a wrx not a sti,tarmac sport has a lot stuff to fit your car.
http://www.tarmacsportz.co.uk/subaru-08-10-impreza.aspx