Please help me with this problem:
I have got a new laptop with a winmodem, which doesn't work.
I can buy a 'real' modem from a friend for a small amount, but this laptop doesn't have a serial port.

Now there are two options:

a) I take the modem and connect it via a serial/usb adapter to an usb port
But i am not sure if this will work at all

b)I get an external usb isdn card. But which one is cheap and easy to
install?
I read about the following ones working under linux for example:
AVM Fritz!Card USB
Eicon Diva 850/852
Draytek Vigor 128
Leonardo Web Shuttle II

Please help me with your suggestions!