My few W/Cs took about six months to get feeding regularly. Luckily they were 'big girls' before then so it didn't take as much of a toll on them as the lighter ones. They are now feeding on F/T or live rats and mice (not picky in the slightest) but they still won't eat if you watch them so I always feed them right before I go to bed so the whole house is dark and quiet.

I do agree to start them out with a small gerbil or a small gerbil scented mouse (one of mine took a gerbil scented mouse lucky me, but I think she's just a glutton). Frankys link is quite spiffy actually, nice info.