Unfortunately, pricing a website can be compared to 'how long is a piece of string?'. There are many factors which can affect the price of the website, for example 'do you require content management?', 'will you be selling and accepting payments online?', 'is there need for an extensive database behind the scenes?'....and so on.
However, to give you an idea, simple websites which consist of around 5-6 pages with a contact form and basic content management will cost from around £500 to develop.
More detailed and complex websites, such as online shops, directories, social networks and database sites can cost anything from £1000 to £10000+.