hey mate, i`m playing resto druid myself(just got back after 4.0.3a because of the merged battelgroups, and well i joined 2 wsgs not going oom quickly, but thats because i drink every time i have the change to just stock up mana drinks and drink every time you are out of combat just to get yourself some mana, i have a spirit weapon for the nice mana regen if i dont get out of combat, think about that to and don`t stack up on spirit, its a nice stat to have on gear but don`t prio it only if you go oom in less then a minute while healing 4 dps.
just my 2 cents