From time to time, I have a need to extract a .MSI file in order to customize a deployment or directly import any .INF files into the driver cache in SCCM. Instead of searching for any uncompressed files within the Windows temp directories, I have found it is much easier if you leverage MSIEXEC.EXE’s administrative install option:
msiexec.exe /a [Path to MSI] /qb TARGETDIR=[Extract Path]
/a – The switch responsible for performing an administrative install AKA “Extraction”.
/qb – Displays a quiet basic UI.
TARGETDIR – Specifies a target directory to “install” the extracted files.
Here is a link to Microsoft’s MSDN site which details further switches you can use with msiexec.exe.
Also, while we are on the subject of MSI files, I recommend you work with ORCA for customizing your own transforms. This tool is only available with the Windows SDK Components but here is a link to download the orca.msi file by itself which is the only file you’ll need.