Hi, can anybody recommend a book / other resource which covers the general maintenance and simple repairs of a violin. I have no idea how to change strings or what wear and tear to look for.
All suggestions greatfully received.

I am guessing you may not have had a violin long, but presumably you are having lessons so the first port of call is your teacher.
There are a few videos on youtube and on other violin websites which show you how to change a string, but seriously initially I would ask your teacher, it is not hard but there is the possibility of badly damaging the violin if you do it wrong and the E strings are liable to snap easily if tightened to quickly, too high to start with.
If you have a student violin there is probably more chance of damage as the build quality may not be terribly good even if it plays ok.
For even minor repairs I would find a local luthier to do them, they will usually put the strings on for you when you buy them from the luthier.

Check for any cracks regularly, keep the violin clean of rosin as this will dry out the wood, never use anything alcoholic on the wood of the violin, you can buy violin cleaner but really only need to use that rarely and in tiny amounts.
You can clean a build up of rosin off the strings with a tiny amount of cologne or string cleaner on a little cloth. Treat your violin like a delicate bird, be it wooden , and never apply too much pressure on any part, or drop it!

There are probably books but I would not attempt to service my own car even with a book!

After some repairs to my viola last summer it was recommended to me that I have it serviced once a year by an experienced luthier. This year when it goes for its service I'm going to have a little adjustment made to the bridge. The luthier will also have a look over for any other problems that I'm not aware of.

I would say changing a string is about the only thing you want to do yourself and Toscaviolin is right - the best person to show you this is your teacher (although a luthier could too). Anything else would be best handled by the professionals.

However I do have this book click here and can very much recommend it for general information on care and choice of instruments.

After playing I always wipe my strings free of rosin and with a clean cloth gently wipe over the viola and chinrest to clean off fingerprints etc. While doing this I would notice if there were any cracks or dents (horror!!) Always loosen off the bow hair too and keep it all tucked away in the case for safety.

Thank you both very much, I have never heard of a luthier. I wouldn't attempt to service any part of my dd's violin but would like to know how to tune/ change strings as it is a long time without practice if a string snaps the day after her lesson, if we have to wait for her teacher. I will check out your suggestions and thanks again.

Although strings and perhaps rosin may be cheaper online, it's good to know somewhere local for emergency bridge rescue operations, re-hairing a bow, and so on. I buy e-strings locally when I can, and our local luthier was very helpful in showing me how to change a string efficiently when sons were too young to change them themselves.

A luthier is a craftsman who makes/repairs/maintains string instruments

Some things wear out. On the violin, these are strings and bow hair. Think of these as an oil change or new brake pads on a car. Annoying, but necessary to keep it working as it well as it should.

There's no other 'maintenance' that needs doing. Repositioning the bridge occassionally, as it gets pulled out of shape by retuning, is a job for you or your teacher. If the bridge warps, then that's a special job. Keep an eye on all the joints around the body of the violin for any sign of joints opening, which is a particular issue with older instruments. Other than that, just keep playing.