Clearly, you aren't going to download it. And, SP3 requires at least
SP1a.
So, you need a CD for SP1a (or SP2) and SP3.
There are two ways to do this. The first, and probably fastest and
cheapest, is to find someone with a fast connection who can download these
and burn them to CD for you. If you don't know anyone personally with
such a connection, try an internet cafe or a computer store. This way,
you can have the disks in a day or less.
Perhaps you know someone who works in an office and can do this.
The other choice is to contact MS and pay to have them ship you these CDs.
You will pay, and you will wait.
HTH
-pk