Copy n Paste time date/time format

Hi,
I have a cell with both date & time "10/9/09 3:15" This is put in the current cell by formula which indexes two dif. cells, Now I am trying to copy this cell and paste into another book but like to have only date. How can I do that?
Each time I try it gives me the time value in the pasted cell and I cannot even format it. Please help.
Thank
Jaz