c1  c2  c3
1   3   5
2   4   6


fp = NotebookDirectory[] <> "Book1.xls";

excelSheet = Import[fp] [[1]];
t1 = Grid[excelSheet, Frame -> All, Alignment -> Left,
  Background -> {None, {Gray, {White, LightGray}}}

c1  c2  c3
1.  3.  5.
2.  4.  6.