Excel's column width is measured by the number of zeros (0) that can fit in the cell at the Normal style. To convert to points (how row height is measured), see
http://www.dailydoseofexcel.com/archives/2004/06/01/column-widths-in-points/
If you don't need to be exact, just eyeball it. If you do need to be closer than eyeballing, put a square from the Drawing toolbar on your sheet and size it. If you want it 10 x 10, use code like this:
sheet1.Shapes(1).Height = 10
sheet1.Shapes(1).Width = 10
sheet1.Shapes(1).Top = sheet1.Shapes(1).TopLeftCell.Top
sheet1.Shapes(1).Left = sheet1.Shapes(1).TopLeftCell.Left
Then you can manually size your row and column to fit the square and read the height and columnwidth.