Usual story, I'm afraid... AmE uses only 'on'; BrE uses 'on' and 'in'. If pressed to identify a difference, my BrE-conditioned brain might hazard a guess that we tend to use 'in' for smaller, narrower streets that enclose ( "My house is in a quiet residential street"), while we use 'on' for wider main streets ("There's a Starbucks on every High Street now"). The other part of the usual story is that there isn't a hard and fast rule, it varies from person to person, and it's changing all the time. My other guess would be that younger BrE speakers probably tend more towards 'on', having been exposed to a greater concentration of AmE influence over their lifetime. In fact, the only consistent thing is that AmE users will tell you that 'in' is wrong.

I would generally agree with Suki, and I am also trying to think when I would say 'in' and when I would say 'on'. I think I would tend to say 'in' if 'street' , 'road', 'avenue' , 'lane' or something similar is not part of the name of the street, for example, there is a street near me called 'Bushey Royds' I would say someone lived 'in' Bushey Royds. Also, with your example of 'HIgh Street', I think we Brits would normally say 'THE HIgh Street', we would add the definite article to this name only, probably because the High Street is THE street, the main street in town. So 'I live on the High Street'

I live in a house. I live on High Street. I live at 345 Lois Lane. If I am homeless, I live on the street.

I agree with Su.Ki. In and on are both used where I am. There is no general rule which to use and as Su.Ki mentions, usage will be different between different people. Personally, I say both "I live in High Street" and "I live on High Street". Where the street is tiny I would always say "in". I tend to always use "in" when I'm talking about a lane or an alley. Probably because in my mind I envision them as small or restricted in size. For a road I generally say "on" unless it was very small and then I would say "in". So as Su.Ki suggests, there is really no hard and fast rule.

I would use "in" a street. I walk in a street BUT as someone has just pointed out, I live on High Street. I walk in a road but I live on a Carcoola Road.