Doing it w/o code behind is not going to be probable if not impossible (I think).
Couple of things you may want to consider:
Handle the item onChanged event of the dropdown and pass the selected item of the dropdown into a stored procedure to return that particular users websites and populate the list box based on the values that are returned.
You may also want to consider looking into Data Relation, however, I don't have much experience using data relation with Datasets and such, but it may be a viable option for you.
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Read this if you want to know how to get a correct reply for your question:
http://www.catb.org/~esr/faqs/smart-questions.html
^^Took that from planoie's profile^^
^^Modified text taken from gbianchi profile^^
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Technical Editor for:
Professional Search Engine Optimization with ASP.NET
http://www.wiley.com/WileyCDA/WileyT...470131470.html
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Why can't Programmers, program??
http://www.codinghorror.com/blog/archives/000781.html
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