I think I found a solution, may not work for me, but it works for others with the same problem - a PCI modem. You do need windows on the machine that you have the Fedora instalation on though.
Go to http://www.pcitree.de
and download the program. Then once you got it installed (you got to copy hpl.sys or somthing to System32/drivers), run it, and find your modem on the list. It should be something allong the lines of Communication Device (followed by information about it.) Hold your mouse over it for the aditional text, and look for something inside brackets like [ ] inside will be the name of your modems chipset. Then look at the numbers and such abit to the left and right of the chipset name. Write them down.
Next, go to http://start.at/modem
go to one of the mirrors, and scroll down to where it says 'view the PCI list', click there. At the top of the modem list, click on the chipset database link. Find your modem's chipset on the list and download some drivers. Get them to your Fedora partition somehow (i'm not sure of anyway to do this but copying the files to a floppy or cd... apparently it can be done by putting it in C:\temp, but that didnt work for me.)
Once the files are in your Fedora partion, follow the steps in this guide
if you don't know what your doing.
That should be it. I hope this helps some people that are having similar problems. This also works for ISA and PCMCIA modems, I think.
**EDIT: Just relized that the list is only for dial-up modems. It does not contain chipsets used by ADSL, DSL, etc. modems.
Further - CRAPTASTIC - turns out the guys who made my modem, Medialight Inc, don't exist anymore! I can't find any drivers for their products, and searches only show manufacturer ID lists. I don't think I will be connecting to the internet with Fedora without purchasing an external modem. Might aswell close this one.
Thanks for the help ghenry.