Refer-a-friend

Hi Everyone,

I am currently looking to implement a "refer a friend" feature to my website, with the incentive of giving away "store credit" for each referral.

However, I am currently looking at an efficient way to code this, however my server side scripting ability is a bit limited.

What I was thinking was something along the lines of the following:

Initial customer signs up -> get's option to join refer a friend program -> can create affiliate type link to my site -> they send this to their friends -> if their friend joins my mailing list their refer a friend account gets credited with a "credit" which they can redeem later on (I can do this bit manually).

Now I expect the best way to do this is with some kind of php form linking to a mySQL database in order to add members of the program and track their affiliate clicks (I imagine I can hack some code into the submit routine for my squeeze page).

Does anyone have any ideas on the best way to progress with this, or if there are any similar, low cost, products out there that might be able to do this for me? (I am waiting for a call back from a sales rep at extole.com, which seems to be the main commercial company doing this, but if you have to ask for a price that always concerns me!)

I look forward to hearing some ideas.

Thanks,

Si