There's been a few posts relating to modding n/a's for performance so i'd do a search and see what comes up.
Styling wise your not gonna get stuff like Lexarse lights etc, main stuff you can do is clear front indicators/sidelights, smoked repeaters, then have a hunt around for an airflow/spg body kit & bumpers for sale.
There's also a few posts about which alloys you can fit on so again have a search and see what type people recomend, i've got a front handbrake model so the sizes are slightly different.
Have fun, don't worry if you start hearing wooshing noises in your sleep & waking up in a cold sweat, that will just be the onset of the DBS - Boost Deficiancy Syndrome, very commom amongst Saab 900 n/a owners:cheesy: .
Oh yea, Velcome to Saab Central, a ha ha haaaa(said in a Count dracula from sesamy steet kinda voice:lol: )