Find very specific usages of things with Package Dumper
Package Dumper is a tool that reads package files and dumps their contents to text files, which allows you to use tools such as GrepWin to search through them for specific instances. An example for why you would want to use this is for finding what file contains a specific named instance of an object, or if you are trying to find what object contains a specific property value. It's also incredibly useful for finding things in ME1's very convoluted filesystem.
You can create a package dump by dumping the entire game or by selecting specific files. You can also drag and drop files onto the interface. Ensure you a disk space to spare as package dumps will take more space than the files they are dumping in most instances.
GrepWin is an excellent tool for searching package dumps. It uses a myriad of options to filter down what you want and is very fast and efficient.
Some important parts of the interface are shown. Ensure you are searching all file sizes, use text search (unless you know what you're doing and want to write a regex). Learning how to use the file names to match feature can cut down on search times and produce less "false positives" if you know info about what you are searching for. If what you are looking for is case sensitive, try the case sensitive option.