I am now at uni so usually not in Newcastle during term time, but if you need to stay here let me know. Depending on my family situation we won't always be able to host you but do our best. I suppose the maximum would be about 3 people. We live in a medium-sized house in a pleasant suburb just 10 minutes from the city centre by metro or a nice 45 minute walk into town across the big park in the middle of the city.
The city itself is one probably one of the best cities in the UK for a short-break. It is relatively small but ridiculously close to the coast, the beautiful countryside of Northumbria (where you can find a large amount of Roman and medieval architecture: forts, Hadrian's wall, castles, churches etc.) The city of Newcastle itself has some lovely buildings of varying eras (as well as plenty of not-so-lovely ones...) and also is a good example of a post-industrial city, but you can still also see many areas which though completely safe to walk around have sadly been left behind by 'development', so it is a good place to get a flavour of the 'real' UK.
The people are also known for being some of the friendliest in the UK and there is also a great cultural scene. Local folk music traditions are very popular and for example you can find pubs where they play folk music most nights of the week, and the price of a pint is cheaper than in London or Edinburgh! (Though I would still recommend visiting both those places) As well this there are lots of other types of musical performances, a couple of independent cinemas, fairly good places to eat and lots and lots of nightclubs (MTV filmed the UK version of 'Jersey Shore' here, if anything you should come for the cultural spectacle...)
You can really do a lot in just a few days here as like I said the city is quite compact. As you can see I quite like the city ;) although I might not always be able to host people I will do my best to make sure you get what you want out of your trip to Newcastle. It can be a good stopping point between London (3 hours by train) and Edinburgh (1 and a half hours by train)