You could preformat the cell as text (format|Cells|number tab|Text).
You could prefix the entry with an apostrophe: '1231234123
Or maybe you could give the cell a custom format:
Format|cells|Number tab|Special|Phone number
or
Format|cells|Number tab|custom
0000000000
(for as many digits as you need)

duckie wrote:

i loose the zero infront of phone numbers how do i get it back

--

Dave Peterson