SQl Server 2005 Express:
http://www.microsoft.com/downloads/zh-cn/details.aspx?FamilyID=220549b5-0b07-4448-8848-dcc397514b41
Microsoft SQL Server Management Studio Express
http://www.microsoft.com/downloads/zh-cn/details.aspx?FamilyID=c243a5ae-4bd1-4e3d-94b8-5a0f62bf7796