Hi mate
I am in N12.
Forgive my short but sweet answers, wee bit busy, work seems to be getting in the way today!
I do not wish to be a prophet of doom! But,
1) Brakes. Bank on a caliper rebuild rather than just changing the pads
1.5) Try
www.wemoto for spares at reasonable prices. Pads, brake rebuild kits, gaskets etc. David Silver?? (tho possibly dearer)
2) Bike shops in london will take your money, perhaps equal to the value of your motorcycle, and do little good. Avoid, unless absolutely necessary
3) Oil on the outside of the motor may not be a major issue, so dont get too caught up about it
4) Good on you for having a crack. Now is the time to learn!!

5) Online guide- no sorry, not an "XBR man", but there is plenty of knowlege here. Anyone else a homepage etc??
Cheers, keep us posted!
a