It really depend's on what you want to do.
You can buy a VPS for your radio which would be quite pointless, but then you could pay for your hosting + shoutcast in one payment.
Once you've got it all setup, providing the host of the shoutcast has some semi-decent user-interface, it's a simple case of paying bills.
You'll need web-hosting and probrely a domain name, I suggest; http://Naxous.com - I would go with the £2.99 hosting package until you've got quite a lot of traffic. Then you may wish to upgrade the bandwidth, but you won't need any more disk space for just a radio, if you've got a fourm + raido + fansite it's another story.
If you'd like any more help in a more detailed convosation. You can add me on MSN.
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