To merge a cell in Excel, first highlight the cells that you want to merge. Then go to format on the toolbar, click on that and select cells. This will open a pop up box, choose the tab alignment, you will then see three small boxes, check the merge cells box. Also look to see if there is a box on the toolbar with a centered a in it. This the button for merging cells in Excel.
eta: You may want to merge the cells before adding the information. Because with Excel you can loose most of the information after you merge the cells together.