findexe is a program for Windows that will find files in %PATH%.
Usage: findexe FILENAME
Requires: Windows XP/Vista, Microsoft .NET Framework 2.0 or later.
License: GNU General Public License version 3
Download binary: findexe-18.104.22.168-bin.zip
Download source: findexe-22.214.171.124-src.zip
You can put findexe.exe in C:\Windows\ to allow access from the Run dialog or Command Prompt.
If you're building from source, you'll have to modify buildit.bat to point to the location of csc.exe.