Amazingly enough, you do what the error message says to do.
Your distro CDs have a package named binutils on them somewhere. Install that package.
Actually, you might be better off restarting your installer (by booting to your distro's CD 1), selecting "upgrade" when it asks, and choosing to install all the development packages. Because if you don't have binutils, you probably also don't have gcc, or your kernel sources, and you might need those.
Installing all the development packages will take space, but it's better to do it that way than fight with dependencies forever.