It looks like you already have some drivers installed for your graphics card that are pulling in a later version of Xorg than the ati-drivers can support:
x11-drivers/xf86-video-ati-7.4.0::gentoo
If you only want to have the ati-drivers, change your /etc/portage/make.conf to contain the following:
VIDEO_CARDS="fglrx"
After doing that, you can try unmerging xf86-video-ati, glamor, and xf86-input-evdev. Then, run an "emerge --update --newuse --deep --with-bdeps=y @world". This should pull in the ati-drivers without all of those nasty conflicts that you are getting. Also, check out http://www.funtoo.org/Package:AMD_Catalyst_Video_Drivers . Hope this helped!