How do I force a column in excel to be stored as text?

All you need to do for this one is put a single quote in front of your text. This also works for dates you don't want Excel picking up.

eg.

'23446

You can also format your entire column as text which will override the whole column. In Excel 2007, hilight your cells, Right click->Format Cells. Click on text from the options on the left.