Please can somebody help, I'm stuck

[#1]

Hi all,
I am getting very confused here.
I have broadband premier so unfortnately dont have any webspace. I have registred a domain with plusnet though, namely cornwallusedcookingoil.co.uk
I have now created a website on 000webhost.com using their webspace and site builder tools.
That site is at www.cornwallusedcookingoil.site90.com
Is it possible to set up my DNS records so that someone entering www.cornwallusedcookingoil.co.uk is taken to my website on 000webhost?
There is a lot of mention on the 000webhost site about changing the nameservers of my domain to match theirs. How on earth do I do this though?
Sorry to sound dumb but this is my first foray into websites and its not going well.
Many thanks
Jules

[#2]

Well I have tried support from 000webhost and they say just ask you registrat (ie plusnet) to change the nameservers to
ns01.000webhost.com 208.43.152.32
ns02.000webhost.com 64.235.48.196
Easy enough I thought. Phone PN support who said send a ticket.
Sent a ticket, expecting this to be easy and had a reply saying that PN can't do this.
What makes me laugh is that PAYH, a sister company recommended by PN says, on their hosting page,
How do I host my domain?
Simply add the domain to your control panel using our easy interface; then contact your domain registrar and ask them to change your authoritative nameservers to:
Primary: ns0.payh.co.uk (212.56.83.195)
Secondary: ns1.payh.co.uk (212.56.83.227)
What's the point in PN selling me a domain on an account with no webspace and not even facilitating the use of another host?
Please can someone make sense of this.

[#3]

PlusNet does not offer that servis, you will need to move your domain cornwallusedcookingoil.co.uk to something like 123-Reg

[#4]

julesandtash do you have access to your domains control page on the plusnet portal ?
If you do then I may be able to advise you of the settings to get it working

[#5]

It would make things much more straight forward to move your domain to a hosting company that also supplies the webspace. I personally would strongly recommend Eukhost with a fantastic, versitile basic hosting package for about £30/year.