Starter/Solenoid how to?

I most likely have to change the starter in my 1999 sunfire gt 2.4 automatic. Does anyone know how hard of a job this is going to be or what tools I am going to need, and any tricks to make the job easier! Thanks!! It clicks a lot and most of the time turns over as if the connection plate inside the solenoid is pitted and not connecting when the solenoid activates, I checked all the connections at the battery already and the battery is about a year old....I am assuming this is my problem....is there such thing as a solenoid kit for this application? Thanks.