You can refer to section "SQL Server 2000 Support Information" in link - http://www.microsoft.com/en-us/sqlserver/support/support-updates.aspx . If you are using SQL 2000, please consider upgrading to latest version of SQL Server as soon as possible.
Upgrade to SQL 2008 R2 - http://msdn.microsoft.com/en-us/library/bb677622(v=SQL.105).aspx
Upgrade to SQL Server 2012 - http://technet.microsoft.com/en-us/library/bb677622.aspx
Is it true that it is impossible to upgrade SQL Server 2000 to SQL Server 2012 ?
If my memory is not too bad, an intermediate upgrade to 2008 is necessary.
Anyway, it is kind to warn the end of the SQL Server 2000 Extended Support ( in April 2012 i think )
Agree with you,
Direct upgrade from SQL 2000 -> is not supported. You need to do an intermediate upgrade.
Upgrade to SQL 2008 R2 - msdn.microsoft.com/.../bb677622(v=SQL.105).aspx
Upgrade to SQL Server 2012 - technet.microsoft.com/.../bb677622.aspx
SQL Server 2000 Support ending soon