If you have the scp program, you can use the following line of code to transfer a local file to a remote computer called the.computer.name:
scp /the/local/file/name username@the.computer.name:/the/remote/file/name
If you don't have scp you can use a combination of ssh (or rsh) and dd. Simply pipe the contents of the file you want to transfer through ssh for dd to copy the file to the remote computer's filesystem.
cat /the/local/file/name | ssh -l username the.computer.name dd of=/the/remote/file/name