Hey all. I found this recently and thought it might help you guys.
Hope they not to out of date.
Short list of mods that you may or may not find handy.
KLH Threatmeter v 20.2
Deadly Boss Mods
These two are mandatory! If you don't already have them, you fail at WoW.
X-Perl unit frames
This gives a new look to the user interface, but has about a billion times more options and functionality than the default UI. My favorite feature is the Range Finder: you can configure it so people who are out of range of your heals are greyed/transparent in the raid frame windows. It'll also highlight who has agro: great for anticipating heals. Has a Rez Tracker too, to prevent dual-rezzing. Tons of other good options; give yourself at least a half hour to play with them and set it up.
HealBot and Click2Cast
These allow you to heal without changing your current target; just assign a button to a heal (I use mouse buttons), hover over the target's frame, and click. Allows for much much faster reaction time since no target change is needed--far fewer keystrokes. I use Click2Cast instead, but it only works with X-Perl; I couldn't find the host site but I have the file saved so e-mail me if you want it.
Emergency Flasher
If you're like me, you always forget to heal yourself. This will flash the outsides of your screen red if your health gets low or if you take a big burst. Helped me save my own life countless times.
Decursive
Cleansing mod. Not as easy (read: brainless) as before the mod nerf, but still invaluable even if you only use it for notification. It'll constantly check if someone is afflicted with something you can cure, and notify you by bringing up the name and affliction in the decursive frame and playing a sound. You can also set it up to cure on click.
Target Check
Lists raid members that are targetting your current target. Good for main tank healing, to keep track of your healing colleagues and anticipate if more/less healing will be needed.
SW Stats
Damage meter. Not specifically useful for healing, but it does get more accurate if more people have it.
SmartBuff
I don't use it myself since it doesn't support totems well (I use Melki's Totem Timers), but I've heard good reviews.
Earth Shield Tracker
Resto-shaman specific, this thing keeps track of your Earth Shield target, charges, and time remaining better than any other.