Q:

Looking for free way to develop Excel add-ins using IronPython?

I don't know much about VSTO or VSTA, but I think you need the full version of Visual Studio to use either one.  I can't convince my boss to buy us this, but I would like to develop Excel addins in IronPython.  I've looked at several tutorials that show you how interact with Excel using IronPython, but I can't find much about developing addins.  Can you recommend any resources?
Is my only option making a COM addin? If so, does anybody know of any example of this using IronPython?
I'm sorry to say I can't go with any options that include spending money.  I've got the free Visual Studio Shell and IronPython tools for visual studio setup for free right now. 

A:

First, you are right, unfortunately VSTO is not supported in Visual Studio Express, the free version of VS.
Then, you may want to look into ExcelDNA. I haven't tried it specifically with IronPython, but it should work. ExcelDNA is a free library which allows you to build xll Excel add-ins and use .NET, up to version 4.

