Damon is right, we'll need some more info in order to have an idea in what direction to go.
For example, you might want a combobox to allow a user to select from a list of, say, names, and then, depending on which name is selected, a cell will say "attended" or "did not attend". The combobox would use the output cell which would be the value a vlookup used to return the status of the name. As the combobox selection changes, the name changes, the output cell number changes and the vlookup returns the appropriate data.
Or, you could be looking for something totally different. Help us help you!