Hi Trist,
Welcome to the forum
Kits are a great way to start building, especially if you have limited tools, space and skills.
Carvin make some good kits, although a bit pricey in comparison to most. Their link is in the UK suppliers section on the forum. You'll have a really good guitar at the end of that. Or you can have a look around at a few others and upgrade parts if neccassary, there are quite a few about. All you generally need for them is a soldering iron and a variation of screwdrivers.
Tonetech do quite a good starter kit too.
http://www.tonetechluthiersupplies.co.uk/Kits/700-Electric-Guitar-Kit-S-Style/flypage.tpl.htmlOr you can look at picking up individual parts although be aware that there are different sizes and some modifications may be required to the parts. Simple tools and a bit of skill required.
The other option is building from scratch which does require a vast amount of tools, money and time.
If you need any help feel free to ask anything and somebody will be here to help
Thanks,
Tom.