In the case for Comet Computing, we run a number of production SQL Servers, so the setup and investigation for Database Mirroring was a requirement since we need to minimize downtime.
Database replication is relatively straight forward to setup with a few "Snafus'".
The big one that seems to get everyone and is what I call the famous 1418 error.
"The server network address TCP://
My simple fix for this after fiddling around for 2 hours for the mirroring was actually reading the documentation more thoroughly (the SQL Server Books Online Help).
The biggest issue is security. All the servers involved with the database mirroring should use the same domain account for the SQL Server Service. Otherwise you have to use certificate and this complicates this. After I fixed this issue, mirroring setup was relatively painless.
The best articles ro refer to are the ones in books online.
database mirroring [SQL Server], configuring
database mirroring [SQL Server], security