Microsoft has published a comprehensive document about implementing failover clustering for SQL Server 2005 and Analysis Services
This white paper is intended for a technical audience and not technical decision makers. It complements the existing documentation around planning, implementing, and administering of a failover cluster that can be found in Microsoft SQL Server 2005 Books Online. To ease the upgrade process for existing users of failover clustering, this white paper also points out differences in the failover clustering implementation of SQL Server 2005 compared to SQL Server 2000.
Get it here