Go for a spax VSX kit or similar
Lowered springs and uprated dampers will drop the car a fixed amount say 40mm no fuss no bother about £250 or about £350 if you go for the PSX kit which is adjustable for damping so you can set how hard or soft you want the ride ( can recommend these, had some very good )
Venommotorsport.com or similar have a good range
Coilovers like the guys are saying about are stiffer and far more adjustable in terms of height and damping etc but are very expensive
Not worth the money for someone who just wants there car a little bit lower