Yes, you are permitted to use the back of your putter.
a golf club
You must mean the ferrule of a club. You can usually knock it back into position with a hammer etc. But if you want a long term fix you can use super glue, or do it properly with golf club epoxy.
Thorney Park Golf club is the friendly golf club house in Iver.
You use a club.
Yes, you can use golf range finders while setting a club record.
Wire wool is usually the best thing to use when removing the finish from a golf club.
Yes, under the rules this is allowed. The only circumstance in which you cannot hit with the back of the club is if it has 2 designated striking faces, this is a club which is not allowed under the rules of golf.
There are a lot of good golf resources out there that break the game of golf down. Here is a good article that talks about every type of club and when to use it: http://www.totalgolfclubs.com/Articles/a-beginners-guide-to-golf-clubs.html