I think it's probably quite normal anywhere.
It's used in a certain case, when you want to talk about being in that moment when something happened.
'I wanted to' is normal but unspecific about the time so that's why 'I was wanting to' became invented, maybe.. so, in certain cases, I think it's totally normal to use it.
People also have invented 'I'm not liking this..(similar meaning to enjoying)' etc for the same reason - a specific situation fo bring in that moment, you know?