MailChimp installed/added to ASPX website quick job

Hi

I already hold a MailChimp account and set-up forms etc..

All i need to do now is program this on the website so when people enter there email address it gets stored in Mailchimp

Have a look at the website

www.tubejourney.com

after entering your email address i want my own design for confirmation but mailed by MailChimp

One did do a form for me which may not be needed. If its not possible to integrate my own design on the website then we can use MailChimp design already done

Here is the Link:
http://eepurl.com/kkLp1

Thanks
AJ