[Closed] Excel Help Needed!! Basic problem driving me mad!!

Right, I have an excel spreadsheet (Excel 2007) that has data in 3 columns (A,B,C,) However in column D I want to copy all the data that spreads across and down the columns A B C into the one column D. This would leave column D looking like this:
D1 =A1
D2 =B1
D3 =C1
D4 =A2
D5 =B2
D6 =C2
D7 =A3
and so on!

So I have done that so I have gone upto D9, highlighted the 9 cells and used the autofill option to continue down column D. However excel fails to see my repeating pattern of A1 B1 C1 A2 B2 C2 and just jumps 3 rows each time so I end up with A4 B4 C4 A7 B7 C7 and so on!

Any quick ways I can populate my column D without having to type it all in??