Subscription payment implementation, Paypal

I have a small work for a guy who knows paypal subscription payments. I have made a user management system on my project. But when I redirect the page to Paypal the value is not coming back from the Paypal API. I need the programmer to make this okay. Also I need him / her to teach me the whole process. You dont need to do any database work, design work. Just posting some values to Paypal and catching the returning values from paypal. You have to create code for Subscribe, Unsubscribe, Upgrade / Modify buttons. You need to teach me data flow and variables of PDT application. Indian client. Lowest Bid wins. Cheers Sourav