Sorry about the double post...this board needs edit buttons quite badly.
But assuming Xorg is already installed, You may want to type in (without the quotes)
that will run you through an interactive program that will ask you for your mouse, where the mouse is connected, What keyboard, video card, RAM on video card, screen resolutions and colour depth desired. After that, I'm not sure what the pre-set (if any) window manager for FreeBSD is, but on OpenBSD it's FVWM2, and after the "xorgconfig" fun earlier, you just type in "startx" to get xorg (your GUI) running. From there, if you're used to Windows, Ubuntu, Mandrake, etc, you might want to use a different window manager than TWM or FVWM or whatever yours is currently set up for. You could go with KDE or GNOME, although it will cost a little bit of speed, but if KDE or GNOME worked fast enough for you in Linux distros, then it should be fine. I myself prefer just simple Window Managers, due to simplicity, speed, and there are so many more...If you like Mac OS, find yourself MLWM, if you're an Amiga fan like me, AMIWM is a good choice. If you like the Windows interface, FVWM95 (other than KDE or GNOME) should make you feel right at home.
If you want, you can PM me sometime and I can offer you more detailed help if you wish.
Have fun with BSD! It's addicting!