You have several options:
1) A firewire card, pretty cheap...but you need firewire output on your source..and VHS doesn't
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You could however borrow someone's DV cam that has analogue inputs on it, thus using the camera as a D/A converting and giving your computer a nice striaght digital feed to work with.
2) A cheap analogue capture card. Most don't have hardware compression...which is a good thing these days cuz CPUs can more than handle the compression...and you can use lossless codecs like HuffyUV. Go with he brooktree/connextant chipset.
3) Trade in your card and get a VIVO version. Vivo is mucho nice
The hardware is the cheaper part these days, the editing software is the pincher. I recommend Vegas Video 5.
Hope that helps.