if I'm in the UK but want to have a sever 12.00pm midnight time to be USA time, would that be unusual, and cause problems, for any reason?
IS this a dedicated server or a virtual server? or possibly even a shared hosting server, we require more information before being able to give such an answer
Then no it would be no issues it's personal preference to what you require - that is if you are not sharing it with another user from the other side of the world who wants it at their time zone
If you are on a Linux server then you can check out this blog post. http://www.cyberciti.biz/faq/howto-set-date-time-from-linux-command-prompt/ You will need root access and a US timezone.