So far I've documented every single Datacron for Republic and even some Imperial datacrons, although the Imperial ones could use more details. I'll be able to post the entire guide on the forums here, but I'll have to do it one post as a time so please resist from posting until I get all the planets in!
Also this guide, since it is going to be posted on these forums can only be text... However I do have many pictures and soon to be videos to support my Datacron guides, but those screen shots are on my website which is here:
I recommend using this guide here for all the easy Datacrons and then the more complex ones that you need pictures for, you'll want to visit my site. Anyway, let's start off with Alderaan!
Aim +4 Datacron
Coordinates: X 1106 , Y 173
This Datacron is located in The Juran Mountains on Alderaan. The Juran Mountains are around central Alderaan so whatever Flightpath you have that takes you right around the center of the map is the one you'll want to take. Depending on your faction there is a bit of running required to get to the start point but hey, who really cares?!
This is a rather easy Datacron to get to; the hardest part of reaching this Datacron is finding the path that leads to the Damaged Lift which you need to take down to the little island that the Datacron is on. The path is across the bridge at the very start of the "Organa Medical Camp". It can be found at the Coordinates 1161 , 230 or you can just look at (Screenshots 1 & 2). Follow the snowy path down to the Damaged Lift which you will need to wait for... I hate waiting.
Once it arrives you need to jump ontop of it, carefully, and then slowly ride it down to the small island that the Datacron is on below. If you're having trouble making the jump wait until it starts down the wire towards the island and jump onto it diagonally. Once you're over top the island jump off the lift and collect the Datacron reward!
Presence +3 Datacron
Coordinates (Of the Thranta): - 406 , 111
This is another extremely easy Datacron to get. In fact all it really requires you to do is ride a Thranta (the big white thing) up to the Datacron. The Thranta that you need to ride can be found around - 406 , 111 (Screenshots 1 & 2). Once you right click the Thranta it will fly you up to the Datacron's location (Screenshots 3 & 4). Once up here grab the Datacron, as simple as that.
Willpower +3 Datacron
This Datacron is located in Castle Panteer which is located in far western Glarus Valley. If you're having trouble finding it, it is where the final quest of Alderaan takes place. In Castle Panteer there is a small little gap between the door and a wall which you can sneak through to reach the Willpower Datacron (Screenshots 1 & 2). Once you make it through the gap head up the stairs and follow the northern path around the room you come out into. The reason you want to do this is because there is a fallen pillar which blocks off the southern route.
Strength +4 Datacron
Coordinates: 2188 , 379
There are two ways for players to reach this Datacron, the first is by buying an item from a vendor for 10,000 credits and the second does not require this item but requires a bit of jumping. This guide is going to cover the second option because it will save you the credits and because if you use the item... You don't even really need a guide. I will however show you where this vendor is located just incase you'd rather take that option. Note that if you do go to this vendor to buy the MGGS also buy the Red Detonite Actuator from him, it is required for another Datacron on Alderaan.
Check (Screenshots 1 & 2) for the location of this vendor. If you're too lazy to look at the screenshots than the Coordinates for this vendor are 1867 , 204. Whether or not you buy the item let's continue now to the Datacron. This Datacron is located at the Lerantha Dam in the Kaamos Territory which is in far northern Alderaan. To reach Kaamos Territory you need to travel north through the Juran Mountains. Once you reach Kaamos Territory you will need to go far northeast through it until you come across the Lerantha Dam (Screenshots 3 & 4)
If you have the MGGS then all you need to do is right click the Magnetic Stabilizer above the Datacron. Your MGGS will pull you over to the ledge and you can jump to drop down to the Datacron. E Z as 1 2 3. Jumping is too, all you need to do is run across the rocks a bit off to the side of the Datacron (Screenshot 5) and jump down to the little metal ledge below the Datacron (Screenshot 6). From here jump up the ladder until you reach the platform with the Datacron and then... *Drum roll* collect it!
Endurance +3 Datacron
IMPORTANT: In order to retrieve this Datacron you will need to buy the item, Red Detonite Actuator from Lain-Ricie who can be found in southern Juran Mountains. A screenshot is below of this NPC.
Coordinates: X 2722 , Y 242
This Datacron is located in southern Alderaan in King's Pass. As I mentioned before this paragraph you will need an item called a Red Detonite Actuator from Lain-Ricie who can be found in southern Juran Mountains. For an exact location of this NPC refer to (Screenshots 1 & 2). Once you have the Red Detonite Actuator travel far south in King's Pass until you come to a cave entrance (Screenshots 3 & 4). Be warned that this cave is filled with elites, it is going to be a challenge and maybe even impossible if you're not at least level 50.
Once you're in the cave go directly east until you come out to where I am on the map in (Screenshot 5). Here you will need to kill the two Killik mobs (or not...) and then arm the bomb via the Blast Pack on the rocks (Screenshot 6). Once you blast open the wall run through into the room and grab your reward!