streaming using video capture device

Hi.

I'm new to the world of htpc so forgive me if my questions aren't well phrased.
What I would like to test is streaming from a video capture device using xbmc.
I went for a capture card as i figured i dont need all the features of a tv card. My set top box does the tuner bit.
Firstly, is my logic correct?
Secondly, I tried to save a stream with videolan and play it with xbmc but it couldnt find the stream, i think. :-)
Lastly, i tried to use nextpvr to record, but nextpvr didn't even detect my device. Would nextpvr only work with a tv tuner?
I have an EasyCap device.
Thanks!