Appling A Formula To The Active Row

Hello,

I am working on creating a excel vba macro that will be used to perform serveral steps, but I am stuck at trying to add a formula to perform a simple lookup. What I have so far is columns A - ?? are filled with data, and there will be different things happening to that data. Then at some point in the process I need to add a few columns to the end of the spreadsheet that will carry out several different lookups. So I am looking for some way to find out what is the last column with data, then go to next available column and add a formula, and then repeat this for the next formula.

Anybody have any ideas how to do this?

Thank you,

Matt