How to watch air broadcasted TV with VLC Player on a Mac
Do you have any particular reason for needing to use VLC?
If you don't you could try EyeTV as it supports a good range of tuners (mine is a miglia) and has a streaming app for the iPhone / iPad 

http://www.miglia.com/
http://www.elgato.com/

Elgato also do network aware tuners