Receiving data from external POST

I'm sure this is a VERY basic question, but it's been a long day and I can't put 2 and 2 together anymore.
I need to accept data coming from an HTTP POST from an external site.  I then need to be able to put that directly into a SQL 2005 database which is hosted on my server.  What's the slick way to do this?  I'm creating a SqlDataSource, but I'm not sure how I should declare the parameter source to accept the data coming from the POST.

Thanks for any help.
CJ

 
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