Reading Properties from an MSI

Hello all,

I'm trying to read properties from the Property table in an MSI.  I've tried using pinvoking msi.dll and using MsiGetProperty but it's not working.  pinvoke is seriously confusing me so I'm just going off of code samples that I've found online and none of them are working.  So I'll lay out a scenario for what I want to do.

A user pulls up a dialog that prompts him to browse for an MSI file.  A file browser appears and they select it.  They then click 'OK' and it shows a message box with the ProductName, ProductVersion and Manufacturer.

The dialogs are created and done, just can't get the right functionality to pull those properties.  A code example would help tremendously.

Thanks!