Hello mmowned,
not really a guide, more a tip really. Right now you can queue for the event bosses without having defended the town. This is likely to be only today since tomorrow is the shattering and these bosses will likely disappear forever.
1) Log on
2) Queue for any elemental boss
3) Get fast JP and 251 loot
4) Laugh at trapped citizen who noone will save now there is no motivation
5) wait for Cata
Enjoy!
edit:
If you're just after Justice Points get a good group and keep queueing for Flamelash. No trash to clear really, just pull em all. Got to the JP cap in no time.