My understanding is that you need a cross site lookup column. SharePoint does not offer OOTB cross site lookup column. You can try third part solutions. Or you can create your own custom lookup column by extending the SPFieldLookup as described in http://weblogs.asp.net/gunnarpeipman/archive/2009/02/13/creating-cross-site-lookup-field-in-sharepoint.aspx . You can also use client side solution as described in http://philwicklund.com/archive/2009/09/08/sharepoint-cross-site-lookup-columns-with-jquery.aspx . Gu Yuming TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com