I have yet to build my pc but I haven't got an antistatic mat or anything. where is the best place to get one for under £20
You don't need one. Just plug in the power supply and touch it occasionally if you're so worried. The only way you're going to generate enough static electricity to do damage to your computer parts is if you're moonwalking over a shag carpet.
really? ive always heard horror stories of someone touching carpet and then frying their whole PC.
I've built PC's on a carpet floor before.
You can also click the case power button a few times (if it’s not plugged in of course) to discharge static electricity.