Dunno if this has been seen by most of us: London's Football Gangs - 1971-2.
And this, we have: http://greatwen.com/tag/skinheads/
The entire site is superb, IMHO.
As a new poster my posts are being held back for 6 hours which is a bit of a pain. Again on this theme I travelled with West Ham to most of the London games between 1968-1971. Never went up North but my younger brother did the trip to Leeds where they pulled the communication cord and jumped off the train before entering Leeds and crossed playing fields to Elland road. All the Leeds mobs were at the station with a welcoming committee whilst the majority of the West Ham fans were already inside the ground. I heard that some of the West Ham boys went back to the station and the Leeds boys were sandwiched.
I remember standing in the Shed with West Ham but we didn't manage to get directly behind the goal which was our target. We also managed to get positioned in the North Bank at Highbury. I can't remember too much aggro. I remember a lot of running backwards and forwards.