Microsoft has just published this whitepaper to give you guidance on automating the installation of SharePoint. Although some might say "Others have already done this" or "I have a much better solution" it provides a good description of the process and, even better, has a good diagram showing the process.

Some of my tips:

• I build the Application Server first which makes it the Central Administration Server (may just be an error by the author)
• Use Powershell (bring on the day we deprecate the CMD shell. Unfortunately I know, it will never happen;-)
• Think about all the default things that probably should be changed and automate the settings (adsutil.vbs is very handy)
  • log file locations (for IIS and SharePoint), SharePoint Data location and index files.
  • IIS Compression settings
  • Web Proxy settings in web.config
• Don't install .Net 3.5sp1 as the base install (which includes 2.0 & 3.0 as opposed to 3.0) as there are a few issues, trust me. You can upgrade to 3.5 SP1 after SharePoint is installed.
• Evaluate some of the CodePlex projects to automate configuration and administration.
  • Search managed properties (use a dummy stp site template with all the list/library columns you want to index , run a full crawl, then script the creation of managed properties and scopes)
  • User profile configuration (I had a customer with lots of custom AD attributes they wanted to import and display in the user profile. The SSP web UI is painfully slow to add and order these
  • ULS Log viewer

We can build a 3 WFE + App server farm from the basic OS in about 1 hour including deployment of custom wsp solutions. It is worth the effort so get scripting...