VBA To Find First Empty Cell In A Row And Insert Text

I'm using Access to export the results of a query to Excel and within the same code I am opening up the spreadsheet to format it. Part of the formatting requires me to find the first empty cell in column A, and then insert the text 'Summary'.

Within Excel, the following code works:

Find empty cell:

Code:
Cells(Rows.Count, 1).End(xlUp).Offset(1, 0).Select
Add term 'Summary' to cell:

Code:
ActiveCell.FormulaR1C1 = "Summary"

I've tried a few different things based on some code I've found on the net from similar situations, but in just about all attempts I get an object defined error. I've tried dimming the piece of code as an object, but when it comes to VBA, I'm just fumbling through.