I'm afraid you are in for a change of springs at least, but I rather guess it depends upon your availiable budget; ideally change both your dampers and springs, and the front and rear anti - roll bars. And then of course, while you have all of these off, power flex bush replacement, change any worn out wishbones, consider if you want to add any strut braces, front upper, front lower, rear upper, etc.
And then you have to chose which springs/ dampers you want ; non adjustable ( Koni FSD are the best of those in my opinion, although I recall something about a bad batch of those, so be aware), adjustable ( massive choice there, from simple stiffness adjustment to genuine race units with variable rebound adjustment). Match your springs to your dampers; race builders will decide on their own poundage rates of springs and mix them up with dampers, but will then spend a lot of time testing, corner weighting and tweaking before they arrive at the characteristics they are aiming for, and I'm guessing you probably aren't heading down that road.
To cut a long story, since I wasn't planning on going circuit racing ( at least, not in that car!), I went for the following spec for my 156 jtd: Eibach anti roll bars, Koni sport lowered springs, Koni FSD dampers, power flex bushes, upper front strut brace, lower rear strut brace. I think it is nigh on perfect ( for a road car), since it is still a comfortable distance eater, but is more than capable of embarrassing far more expensive vehicles on the twisty bits. If you shop around a similar spec for your car will probably cost you roughly £1200 or so. This will increase if go for adjustable shocks. Then you'll want an LSD....and better brakes...and a remap.....etc, etc!!!
Good luck, remember a good way to end up with a small pile of money .....is to start with a large one and begin modifying your car! So decide what spec you want, and buy carefully!
Best of luck
Hope that helps!