when I try to download the drivers via your site, via learning, after download teh windows7 software,i try tp download te drivers for Duemilanove. however i seen el lot of messages appearing over sceen, all about identification etc. but no download comes in. Ik have created an arduinostore account.
so! what now?
kind regards.
T.H.M. Tempels.
hi
the duomillanove uses at usb a FTDI232 Chip, so there is no "arduino-driver" necessary.
go to FTDI (google them) and there will be a driver for nearly every operatingsystem. in windows arduino environement you set tools-serial-port to the comport you found in device-manager of windows (you see the device if it is connected, every duomillanove gets a new com-port)
after that you have folowing 2 problems:
if you disconnect while the port is opened you have to reboot
sometimes you go to the tools-menu you have to take a cup of coffe or cut the grass in your garden. this can be patched by another serialxxxxxxrxtx.xxx i never know.
if you want to do more with your duomillanove change to linux 
best regards
w
http://www.ftdichip.com/Drivers/D2XX.htm
I think you want the D2xx drivers. Or the VCP drivers.
I'm on the road with no devices, can't tell you which my WinVista or Win7Pro uses, other than that's 2.12.0
You could also use the Arduino/drivers/FTDI USB drivers that come with the IDE as a starting point. I used the driver that installed with IDE -0021 for a very long time on my WinVista machine.
Are you using 1.0.6 or 1.5.8, i have had better luck with 1.5.8