So I don't really use too many macros, I only really use ones that let me clean up my action bars slightly, and one main one for Earth Shield
First I use a macro that lets me cast water shield when I click it, or if I'm holding the ALT key it casts lightning shield. Here's that one.
/cast [mod:alt] Water Shield; Lightning Shield
it lets whatever I'm casting take over the image by leaving it as #showtooltip (I use the "?" icon for the macro icon)
again its just to clean up some bar space. but using the same macro you can alter it to suit many needs.
/cast [mod:alt] Water Walking; Water Breathing
Same principal as the one above it, one button with a modifier that allows you to cast either spell saving your some bar space.
Pre-wrath and before cleanse came and made me giggle like a school girl on prom night we used
/cast [modifier:alt] Cure Poison; Cure Disease
again just a space saver.
now for my trusted Earthshield Focus macro! now I warn you I'm typing this from memory since I'm at work and cant get in game right now to copy and paste it and as a result I will update it when I get home with exactly what I have but here it is
/cast [target=focus,exists][button:2,target=target][mod:alt=/clearfocus][target=focus,help, nodead][target=target,help,nodead][target=targettarget,help,nodead][noexists]Earth Shield
Here's the premise. First target you pick and click the macro button it will set them as your focus and cast earth shield on them. If you right click on the macro, it will put the earth shield on whoever you have targeted and if you hold the ALT key and hit the macro it clears your focus.
That should be the answer to the comment about earth shield focus blues =)
That's pretty much it for what I use for macros, like I said I'm more of a clicker. I had alot more before 3.0 hit. I had ones that swapped out totems for different heals and allowed for total min max, but that's been removed in the current build of the game. =(
Hope this helps