I lived in Northern England (outside Leeds) but pretty much only visited Manchester to leave and enter the country via their airport. If you like old tudor stuff though I did go to one cool pub called the Old Wellington Inn.
I'm not much of a city person so I spent a lot of time in the English countryside. Manchester is close to the Peak District and Chatsworth House (from the A&E version of Pride and Prejudice, capability Brown creation) which are both worth a visit. Also Northern Wales has some really beautiful scenery and there are two or three impressive castles close together on the northern coast. Chester is close to Manchester too, it is a cool old walled medieval city - not as good as York but worth a visit.
Sorry if that's not much help. I didnt care for the large cities in England, other than London. But the small cities in the country, the abbey and castle ruins dotting the countryside, that's what I thought was so cool.
Hope you have a great trip