Need someone to integrate authorize.net into payment area

I have a website that is completed done. It's a membership based website where people can come, select whether they want to have a 1, 3, 5 or Lifetime membership. Right now it's hooked to Paypal only. We also have an integrated custom built Promotional Code system built around it all - We have signed up for [login to view URL] and we need that put in as an option when the customer goes to pay - It must ask them if they want to a) Pay by credit card, b) pay by paypal or c) send in a check for their membership. I need this done by tomorrow (Friday) - The earlier the better. MUST BE A PHP EXPERT AND HAVE LOTS OF EXPERIENCE WITH PAYMENT GATEWAYS AND CHECKOUT PROCESSES. No NOT bid if you do not know what you're doing.