When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Starters typically last a pretty long time so it probably is a bad/corroded connection somewhere. I would check the connections on the starter, the solenoid and the battery before looking too much into the starter itself.
What are the symptoms? Do you hear a clicking? Starter acting slow? Starter not turning at all?
If you have a strong battery and the headlights/accessories work well, but the starter won't turn or turns very slowly, it could be your starter. I know it sounds funny but you could also try having someone hit the starter with a rubber mallet while turning they key and see if it starts. If that does work your starter is probably going bad then.
You could also try to bypass your solenoid by taking a screwdriver (make sure its insulated!!) and touching both terminals of the starter with the metal part. If your starter engages then you might have a bad solenoid or connection. If you do decide to do this make sure you are in neutral and aren't touching any metal part of the screwdriver!