vb,net app with excel automation

I have a macro that was developed with a lot of help from others, that copies two columns of data from one sheet to another with the same two columns without overwriting anything. I want the app, fully commented. I am using vbnet express 2008 and still very much a beginner. That way I will understand whats going on and can change the code later on if needed. The macro that I use requires me to copy and paste info from a workbook into a sheet in the second workbook. The workbooks are identical other than the info. Then two colums of data are copied from one to another without overwriting the old data. This is a daily process that takes hours without the macro. I want a couple of buttons on the form to let the user pick the correct workbooks and another to copy the data from the source to the destination without the copy and paste into one workbook ahead of time. You can have a copy of the macro and sample workbooks so you can see what I am doing. I use office 2007. ## Deliverables I've added the macro that I'm using. I would like this done by the Jan 4th 2010. I can send the sample workbooks when you need them.