Easiest options if you don't want to register a domain name is one of these:
- set up a
Posterous blog- alternatively you can use the free hosting from Google and set up a
Blogger- or host your site on
Wordpress.comThe other option is to buy a domain name (~£1.99 for a .co.uk or ~£5 for a .com) and pay for webhosting.
Recommended places to register a domain include
http://www.123-reg.co.ukhttp://www.1and1.co.ukThen you will need to get somewhere to actually host your website -- you can normally find cheap packages that include a domain name and bit of webspace free (eg. 1&1 above)
To set up and host your own Wordpress blog is fairly easy, but you will need to read through the install instructions on
http://www.wordpress.org . Some hosts make it very easy to do this with a 1-click install of Wordpress
Hope this helps