Again, Thanks to Boudicca for this:

Seal form (level 18 ):

This quest was a lot more time-consuming than the first, event though you
don't fight any big mobs or anything. Again, I recommend having a refreshed
Hearthstone to speed things up, and you'll probably have it refresh at least
once during this quest anyway.

Once you're eligible for the quest, the Turak in Thunder Bluff once again
tells you to go back to Dendrite in Moonglade to learn about the aquatic
form. So, you teleport once again to him, and Dendrite wants you to explore
the depths of Lake El'eune there in Moonglade for a shiny bauble, then open
it at the Shrine of Remulos over on the west side of the lake . It's a timed
quest, and you only have 30 minutes to find it and take it over.

Once you find the bauble (and it can be hard with the timer and if any
competition is around), get to the shrine. The shrine is on the western end
of the zone, and Remulos can be seen guarding it. You activate the bauble
next to the tree and then speak to the Night Elf NPC at the shrine. She
sends you back to Dendrite to do the second part of the quest.

Dendrite then tells you to find two halves of a pendant, but he doesn't tell
you where. If you want to see the clues, talk to the Orc Wind Rider trainer
to the South, close to the Timbermaw Pass zone.

I'll divulge the locations of the pendant halves here (OMG Spoilers):

Both halves of the medallion are inside black chests you have to open.

1. The first half is located in the Barrens, at the bottom of the Sludge
Fen - the pond northeast of the Crossroads. Really easy to get once you
clear your way to the water, killing the mobs in your way.

2. The second half is on the coast off Silverpine Forest, at North Tide's,
directly west of the beached shipwreck. You have to swim FAR and DEEP to get
it, so stop at the bubble crevice to refresh your breath, then keep going
west along the bottom of the ocean. Fatigue sets in before you reach the
chest, so prepare to die if you're not fast enough. I died trying to swim
back to shore once I got the medallion, but the important thing is I got it!
(BTW thanks a TON to Ahnn who guided me to the shipwreck, otherwise I would
have spent an additional hour trying to find the exact location in the
forest).

Once you have both halves, teleport back to Moonglade, go to the Shrine of
Remulos, and combine the pendant. Go back up to Dendrite, listen to him
blabber, then port back to Thunder Bluff and complete your quest. Hooray,
you can turn into a scary seal!

Seal form is not useful for anything other than swimming, but it gives you
enduring breath and you swim 50% faster than anyone else. It's great if
you're fighting underwater, you switch over to it instantly to reset breath
and switch back to continue fighting/casting/etc.

umm, its a great guide but i have tried to find sludge fen and all people tell me "northeast" but they dont give me a specific location. So im thinking where in the northeast? i am a newb so dont yell at me coz im dumb

okay, i finally got the half pendant from sludge fen. Now the other half is proving itself very difficult to find. I go to the shipwreck and go underwater when i reach the place that deepwater meets shallow water, i keep swimming and do i see a fissure? nope nothing just crap all. sry if im whinin a bit but can someone please explain this part of the quest in detail?

It is my reccomendation that anyone who plays download a UI with some form of lat/long coordinate tracker.

For the half pendant in Silverpine, the coordinates are 29,29.

The half pendant in Sludge Fen is easy to find. Just swim around for a couple of minutes and find the grey box.

Just a tip for the water part of the quest. I think I made it halfway across The Great Big Sea heading West before fatigue killed me. Then another couple of deaths heading to various distances West attempting to extend my range or find something I missed.

The bubble crevice and the box are actually a short distance North along the main drop off to the Great Sea. You can make it in a single breath from boat to box so you shouldn't have to worry about fatigue. (I didn't, but I teleported right from the box when I found it anyway.)

Now that I have Aquatic, I'm going to see if I can make it ALL the way across the 'Sea =D

It's not possible. You'll die of fatigue.

I just did the last part of the aquatic form (thanks to whoever posted where the damn ship could be found) and I found the box near a bubble fissure. Which was even more surprising was that fatigue never set in. I think blizzard may have changed the location of the box. Just a thought

I noticed when I was swimming out west past the ship, there was an elite level 22 shark, I believe it was 'Reef Shark' inbetween the boat and the fissure. It's no big deal, just time it right and you can swim on past him, but I have not noticed anyone else mentioning this.

Could be something new because I did this quest twice and never saw the shark.

The sharks have always been out there (and near the fatigue area in other zones' coastlines as well). I killed them a few times for the heck of it (at a later level). :P

They have definatly changed the quest. Once you see the shipwreck, swim directly west, and look for the bubbles. The chest is right next to the bibbles now. You don't even get fatigued anymore. I just did it last night.

I'm stuck just trying to make my way to Silverpine Forest. I must be missing something here. I'm taking the boat from Ratchet to Booty Bay and can't go more than a few minutes down the path before being killed by ?? MOBs. There must be another way.

Please help! Thanks!

Silverpine is just off Trisfal Glade in Norther Eastern Kingdoms. The best way to get there from Kalimador is to head to Orgimar and take the zeplin from right outside Org to right outside Undercity. You'll then be in Trisfal. Follow the road towards Spulcher (sp?) and you will soon be in Silverpine.

Thank you!

Did the quest. Seemed like kind of a lot just for Sea Lion form.