It really is that simple, install WSSv3 (with SP1), run configuration wizard, install Search Server Express, run configuration wizard again, set up search server (including indexing) and you’re ready to go. When I did it for the first time, after setting up search, I was getting an error that Search Server could only be run on a single application server. I was doing a single server install so I couldn’t figure out what was going on. Apparently, I had forgotten the indexing setup of Search Server and for some reason, not having indexing turned on and configured throws this error. After finishing up the indexing piece everything worked like a charm.
This does bring up, what will probably be one of the primary downsides of Search Server, is that you can only have one Search Server per farm. Using the Express version you are unable to load balance your search servers. If you wish to set up a Search Server farm, you will need to purchase the full version of Search Server.
As I continue to utilize Search Server, I’ll be posting more on some of the features and configuration possible. A comparison of MOSS, Search Server 2008 Express and Search Server 2008 can be seen here.