Recommendations for MS SQL Server monitoring software or service? I have a client with MS SQL Server instances (2000, 2005) scattered across 20-30 servers. I've been engaged to get things organized and will be periodically reviewing the state of the database infrastructure for health, testing backups, etc. We also plan to get as many of these databases up to 2008 as possible. 

I'm aware of services like New Relic for Linux stack web apps and databases, and I stumbled onto the SQL Monitor product (RedGate) just today via Google. Can anyone provide some direction in terms of services or tools (that you have experience with) that would enable me/my client to monitor and manage their MS SQL instances?
You've got lots of options.  The venders to look at that are SQL specific are:

Quest Software - Spotlight
Red Gate Software - SQL Monitor
Confio - Ignite
Idera - SQLdm
Microsoft - System Center Operations Manager
Microsoft - SQL Server 2005 Performance Dashboard
SentryONE - Performance Advisor
ApexSQL Monitor


They will all do the job nicely, it just really depends on which one works best for you in your shop.  They all have free trials so you can try all of them and make an informed decision.