There are several things keeping us from being more organized about WvW. One is the ridiculous queue times that mean you basically can't guarantee you'll even get into WvW on a particular night. Another is the maximum of 5 people in a party. Beyond that and you have to get people to start extra groups. I believe once we get someone to 100 gold, we'll be able to form a battle group of some kind that is essentially a raid group to help alleviate this.
The BEST thing to do if you want to group up for WvW is jump in mumble and look for the regulars. Just off the top of my head, you have Hawkian, docbon, guymanly, palmer, wollach, etc. We're not always in the right channel for WvW though. We should probably be better about that so it doesn't confuse people looking for WvW. If you're in mumble, you can at least coordinate what's going on even if you're not in the same group.
I also proposed starting a WvW/PvP specific guild to help narrow down who's actually interested in that stuff from the rest of the general guild chatter. Someone you could change over to when you are planning to WvW for a while.