It would probably be easier to write your own server-side search script than use a 3rd party tool. Codeproject is more oriented towards C# or VB script though. To make the query, you need a knowledge of SQL, and any database software will do such as ms sql server, mysql, or postgresql.

For word-by-word diff I like to use the SequenceMatcher class in CPython. It has a method get_opcodes which is helpful. I was able to call get_opcodes in C# using IronPython (uses 5 .py files). I store the PythonEngine in session since the ctor is expensive.

Set a javascript timer to poll a database every few seconds using xmlhttprequest. Use the Document Object Model to insert new text into the browser. You can determine what text is new using a timestamp, hash key, row count, or some combination.

It's under there. Add ASPNET to local launch and activate permissions. With Excel 2007, I found it necessary to login as ASPNET user using a program called anup(gets ASP.NET encypted password), logging in as ASPNET user, and then clicking OK on dialogs which popped up in order for interop automation to work from ASPNET user account.