FIAT themselves do thier own kit, which I think are reasonably priced and are made by EIBACH. Or you can check out these guys!
http://www.motorsportworld.co.uk/
That's where I got mine, tell them you've seen them £20 cheaper somewhere else and they'll match it, the best price I found on the web was £115, told these guys I'd found them at another online store for £89, they said we'll match it and include delivery!
Hope this helps.
FIAT Stilo 1.6 Sport. Pretty Much Bog Standard Really.
Sill Protectors, Aluminium Foot Pedals, Eibach 30mm Drop Springs,
Starsky & Hutch Stripes, Ambipur Air Freshener.