You've to make your mind. The Northwind and pubs are SQL 2000 sample databases. They can be installed on SQL 2005 and later as well.
SQL 2005 and later have new AdventureWorks sample databases. They can be downloaded and installed separatelly.

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>I want to download and add the Northwind sample database to my SQL Server 2005. I am looking at this page:
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>http://msdn.microsoft.com/en-us/library/ms143221(SQL.90).aspx
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>What is confusing to me is when I click on the link in the line "These databases can be downloaded from this Microsoft Web site." I get the following page:
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>http://www.microsoft.com/downloads/details.aspx?FamilyId=06616212-0356-46A0-8DA2-EEBC53A68034&displaylang=en
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>lists the name as SQL2000SampleDb.msi
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>Yet, according to the initial page the file I need is SQL2005SampleDb.msi.
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>What am I missing?