Hi chap
welcome to the detailing section and golfgtiforum.co.uk
your options are fairly endless and you can go as far as you want/your budget will allow and it depends what level you want to get to and how much time you have?!
i'd recommend that you start by reading the following thread
http://www.golfgtiforum.co.uk/index.php?topic=66113.0then perhaps telling us what you want to achieve and what your budget is...
don't forget to refer to the useful online traders section for those who retail cleaning products online
http://www.golfgtiforum.co.uk/index.php?topic=64295.0