You have LOTS of ways to do this, depending on the your requirements. You are basically building a distributed app, and .NET has some very strong technologies for this.
First of all, the most simple solution is to create a shared folder, and then create a program that uses that folder for communication (periodic checks for changes, etc...)
Second solution would perhaps be a ASP.NET web service, also depending what info you want to share.
At the end, the most powerful solution would be TCP/IP Sockets, but that is really for VERY fast, and VERY concurrent requirements.
Since you didn't fully describe what you want to do, I suggest you do a "distributed programming .NET" or "network programming .NET" search on the Google.
There are plenty of examples using all sorts of techniques, either in VB or C# (and you can also translate code from one to another).