I ordered the eibach sportline springs and I'm wondering if there are any parts that I NEED. I'm not too familiar with suspension parts so I'm not sure what i need....isolators? caster camber plates? ball joints?
What he said. I'd say with sportlines you will probably end up needing the Caster/camber plates but you won't know till you go to get an alignment. Which you will definetly need after the spring install.
I have a ProKit and need CC plates so I'd also suggest you get some. Even if they are not needed for 'spec' alignment settings, they are needed for performance-oriented settings.
Poly Isolators are nice but will add a little height to things. If yours are in okay shape and money is real tight, you can likely get away with the stock isolators (even if they require some patch work).
And that's about all I used on my last spring install.