Stage 1 is just a tune. You can go open source which you need a laptop and a tactrix cable ( ECU Tools ). Or you could by an accessport ( CobbTuning.com - 09 AccessPORT ) which is plug and play.
Stage 2 is a downpipe, you can also add catback exhaust to get a little bit more power.
Stage 1 - Tune (about 250-260 HP/TQ to the wheels)
Stage 2 - Downpipe and a tune (290 - 300 HP/TQ to the wheels)
I have an 09 and i got the AP to go stage one. I will eventually sell it and go opensource once i start doing more mods.
with 1K you can get a full Exhaust (DP, Catback) and a tune... which would put you at stage 2.