Toyota camry 1999 does not start

Question

Hello,

  Yesterday, I parked my car outside, and I was not able to start my car today. First, I thought that my battery was dead, so I take my battery to the Auto Parts Store, but they told me that my battery is working OK. Then, I took my stater to them to check , and they checked it and told me that stater was not good. When I asked what was wrong with it, then did not tell me anything. So I am trying to find out what is going on with my car, and Could someone give me advice or directions? 

So far I did the following things:
1) Battery was checked by Auto part store, and it is ok
2) Starter was also checked By Auto parts, but they told me that it is not good.