l have a 2002 bmw 325xi and it didnt come with the phone handbook
does anyone know how to set it up

First u have to check if ur car has the telephone (bluetooth) option.Frankly l doubt that ur car has it for this only became more widespread in BMW is approximately 2004.
To be sure, check ur car is list of options. Or ask u nearest dealer.
Or look for the TEL/TCU module (an aluminum box approx. 2 1/2 '' thick x 4'' wide x 10'' long) inside the trunk is left side trim cover. But even if ur car has the TCU, it still needs to be programmed to work in ur car & for this u need to see a dealer.