I think that what you've posted explains the situation... There are several issues here, which I'll try to break up:
1) The Intel wireless drivers. These consist of two pieces: one is an open source kernel module, which activates the wireless adapter by loading the (closed-source) firmware on to the adapter chip itself at boot-time. The second file contains this firmware.
The good news: Getting this hardware to work on current distributions like Ubuntu 6.06 and FC5 is painless. The open source part is now part of mainstream Linux. Ubuntu also includes the closed-source firmware file, so the adapter works automatically. As a pure Open Source product, Fedora does not include the firmware file so you just download it separately and unzip it into /lib/firmware/, then reboot. Alternatively, third-party repositories provide RPMs that will install the necessary file for you. Install the NetworkManager software for automatically network scanning etc.
Fedora instructions for setting up an IPW adapter and NetworkManager are here:
2) The error messages. "HSF" relates to modems. Modems are both network devices and audio devices (they output beeps etc.). It looks like you have tried to install modem drivers which are interfering with the existing audio drivers (for the integrated Intel sound card).
3) modprobe.conf and aliases. If you didn't know, config files have man pages just like programs, man modprobe.conf explains the syntax. On Fedora network drivers have aliases that match the name of the interface: "eth0" etc.
4) The modprobe executables. Unfortunately I don't have an FC3 system to check, but I only have /sbin/modprobe on my FC5 system.
To be fair, Linux hardware support often just works. We only notice when there aren't open source drivers available for particular components, and have to manually load whatever proprietary software the hardware vendors chose to offer in lieu of proper support.
Intel generally puts effort into ensuring good Linux support, and the decision to make us jump through hoops with closed-source wireless firmware on the IPW devices is not typical. Supposedly they have to restrict code access in order to comply with FCC regulations on wireless devices.
Some other hardware vendors seem to be generally reluctant, and will probably only change their attitude when Linux attains a bigger share of the desktop market. Or large customers begin to insist on open source drivers as a general principle, which they should for security reasons.