Using URSP for subscription Membership via PayPal

I've set up a site that uses URSP to register to gain access to certain pages of the site. No problem there.

I know need to set up a subscription service via PayPal. I've already been assured that this can be done. I know that I can create the buttons etc for one, six and 12 month memberships. I also know that I have to create an IPN listener page and I know the principal of how that operates. PayPal sends the info, the IPN listener on my site sends the exact same data back and then PayPal sends a VERIFIED message.

My problem is how do I write such a page and then how do I set the URSP database fields to the correct subscription? I've spent two days now in reading and Googling but I'm none the wiser for my efforts. Has WA got any tutorials on how to do this? Failing that is there anybody out there who would be willing to hold my hand in this venture. Or failing that is there anybody who would be willing to accept a fee for doing it for me?

I really would be most grateful of some help. I do have access to the entire WA Library.