I use a 56k usr external modem. It works great. I think they cost $90 new. RH9 autodetected it. I only had a small problem when I first installed it, which I fixed after reconfiguring my IRQ's and playing with the jumpers switches on the back of the device, and playing with the setserial command. --those problems might not be an issue for you if you get a new modem with a manual. (I got mine used)
External modems are reccomeneded over internal modems anyhow. They are self-sufficient and require less system resources to function.
