This could sound a little late, since you may have found a solution on that.
I own the same machine and I am in the middle of installation of Archlinux. I choose i686 since the 64bits support on the Intel N450 seems to be partial and the CPU could be not able to cope with increased work by 64bits-only calls.
The wireless driver should be
wl. It is possible to install that quite simply, but before that you need a working connection (best solution is probably ethernet, since it's automatically recognized and configured).
After base installation, you need to install yaourt following the instructions on ArchLinux.fr site.
Then you can simply call:
yaourt -S broadcom-wl
More details on this page. A pair of minutes just to compile the modules and you are ready to go :)
Please be aware that I need to fix names of interfaces after adding the drivers to the MODULES array in /etc/rc.conf (it reverses ethernet with wireless, calling the wifi interface
Hope this will help.