Hello Gavin, welcome to the forum.
Did you notice that the post by CyRob was dated 13 February 2009??
There's been a great deal of major changes to the immigration rules during the intervening 4 years.
May I very kindly suggest you read through this thread - All New Guide - How to apply for a Fiance Visa
Please do follow all the included UKBA links.
I hope it will provide a better understanding for you. If you have any specific questions you'll receive a good range of responses by starting your own thread.