how can i find out more about a person online for free?

[Nick]

What is the era of the pencil case? That will give you some clue as, presumably, he would have been a schoolboy when he owned it so if you can put a rough date on it then you have some indication of what age he would be now and when he may have lived at that address. Old telephone directories might give you a match for Robinson at that address. At a guess the British Library would have an archive of these.