A while back someone asked for a good source of power and data cables for GPS units. Here is the place I have been getting them from.

http://stores.ebay.com/RNRPLACE_W0QQssPageNameZl2QQtZkm

It is an eBay store but you don't have to bid - their "Buy It Now" prices are very reasonable. I have purchased several cables from them for myself and others and they have all been good quality.

I just ordered a couple more power cables today for less than 1/3 of what they are from Garmin.