Thanks UCLASnerd, and looking good!
Check out this PS seminar I did on selective sharpening- it's the most advanced seminar I've done, but the technique works excellent once you get it down... and it's really not that hard.
Photoshop seminar 3- selective sharpening
I wish I could do a seminar on the healing brush, but there's really no way to show people the technique without doing it real-time. A couple hints- definitely use a smaller brush size, whatever size is just large enough to cover the blemish you're healing out. Also, when trying to heal something near an edge- say, the outline of the fish- try actually alt-clicking with part of the brush on the edge of the fish. That will help cut down on the "volcano of color" effect you'll get sometimes when trying to heal near an edge. HTH.
Travis