HD TAPE DECKS are very expensive. http://www.amazon.com/Sony-Professional-HVRM25U-Record-Playback/dp/B000FTLMT4
Your cheapest solution is to get a camcorder of the same make and model that made those tapes.
Bob
Is there a way (device?) to transfer HD mini DV tapes to my computer? I have a Sony Handycam camera that is not HD. My son has about 50 mini DV tapes that were taken with a Sony HD camera. The HD camera doesn't work anymore, and my camera will not play the HD tapes to the computer. I don't want to invest in the older technology HD tape camera, but I want to get these tapes backed up on an external drive. Any suggestions?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic