Brian,
This is usually not a starter issue, but replacing it is not too hard although, I have not done one on your model. I still think it is not enough juice getting to your starter. This is a shot in the dark but sometimes a good whack with a hammer on the solenoid can get your starter going again. If this works then yes you will definately need a new starter. But as I said earlier I still think this a lack of juice. A bad ground cable could definitely cause this as could a bad connection to the starter.
m

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Martin Ingram
Colorado Springs
2005 320 CDI
2006.5 VW Jetta TDI
1991 560SEL (179000 Sold)
1972 280SEL 4.5 ('The Lead Sled' 320000 miles when sold.)
1972 220D (225000 when sold)