Post by inthane
If you're dead set on healing, and you don't want to spring for dual spec (if you go dual gathering and put everything on the AH, it's doable by 40 if your server market is decent) then you're going to have to make some choices. The question is how much offense do you want to trade for heals?
I'd suggest going up the Balance tree, since there is some synergy there between Balance and healing. Genesis, Nature's Majesty, Moonglow, Nature's Grace, Nature's Splendor, and Celestial Focus all help out a little bit with healing. I threw something together just off the cuff - it's not going to be extremely powerful, and quite frankly you're going to lose solo power over a more dedicated soloing spec, but it will get the job done, sort of - check out this link:
http://www.wowhead.com/?talent#0tG0uzhZZfV0uUntil you can get dual spec, keep pushing up the balance tree. You're not going to be the world's greatest healer, but it will do for most instances for a while. Really, the way to go is dual spec, with feral for leveling and resto for instance healing.