Ian is located in Qeynos Harbor, he is standing outside the door of the building we had to enter for the end of our predator quest, the "cache".

Ian's Forgetful Family - Part I

-Kill 20 Caltorsis Knights
-Kill 4 Sabertooth Tormentors

Reward: Trade Link Gauntlets- 79 AC at lvl 25, +4agi, +3wis, +13 health, +11 power, +84 disease, +67 def. vs heat

Takes place in Antonica.
Caltorsis Knights can be found near their keep, just east of Oracle tower.
Sabertooth Tormentors have to be spawned, they do not exist on their own. If you are standing in front of Blackburrow, facing North, there are two camps of gnolls to your right and left. Each camp has 4 groups of gnolls. Pick a camp and kill its 4 groups of gnolls before any of them can respawn, effectively wiping the camp clean. This will cause 2 Sabertooth Elders and 2 Sabertooth Tormentors to spawn near the tents, wipe them out and start over for your second set.

Ian's Forgetful Family - Part II

-Kill 25 Giant Kodiaks
-Kill 4 Broodtender Spiders
-Kill name gnoll Grolven Chiptooth

Reward: Trade Link Bracers- 123 AC at lvl 26, +4int, +3str, +13 health, +12 power, +101 def vs divine, +50 def. vs poison

Takes place in Antonica and Blackburrow.
Giant Kodiaks can be found in the very Northeast corner of the zone, just NW of coastal grove and North of Fangbreaker Keep.
Broodtender Spiders are in the depths of Blackburrow, once you zone in you will see a waterfall ahead of you, jump into its pool (watch for ledges on the way down) and climb ashore near the spiders you see there, a tunnel to the left will lead you to the Broodtenders, you will need a group as Broodtenders have their "brood" with them.
Grolven Chiptooth is a tough named gnoll who wanders just outside the entrance to Blackburrow, if I'm not mistaken he is lvl 21^^. Take a group of 20+ dmg dealers and healers to take him down, as he hits very hard.

Ian's Forgetful Family - Part III

-Kill 12 Defiled Knights
-Kill 5 Defiled Crusaders
-Kill 10 Defiled Cavaliers

Reward: Trade Link Boots- 85 AC at lvl 27, +5sta, +3agi, +16health, +11 power, +84 def. vs magic, +67 def vs mental

Takes place in Stormhold.
Defiled Knights can be found in the chessboard room, accessable from the last door on the left from within the main hall (main hall = first room with actual doors in SH).
Defiled Crusaders are found in the halls and rooms near the library entrance. To get here, take the last door on the right in the main hall, proceed until you find the door that leads to a spiral staircase going down to what's called the second level. You will soon come to the "atrium" which has many doors, I recommend taking the door on the left, and then going right when you come to the room with a pool of water at the base of the stairs.
Defiled Cavaliers. Following the path mentioned above for Crusaders will bring you to a room with two staircases going up to a turret (castle style). Cavaliers will spawn on these two sets of stairs, the door above eventually leads to the chapel, for reference.

Ian's Forgetful Family - Part IV

-Kill 25 Deathly Scarabs
-Kill Several Forsaken Shrillers
-Kill 15 Restless Corpses

Reward: Trade Link Mantle- 132 AC at lvl 28, +4sta, +4wis, +14 health, +15 power, +101 def. vs cold, +50 def. vs heat

Takes place in Crypt of Betrayal. Get here by entering Vermin's Snye, take the spiral stairs to the upper door. Proceed to the first big room and take a right, you will eventually come to the end of a tunnel with a left turn leading to another "pool" room with undead, one of the grates in the water will let you enter. (note: this is the first of two, and "newb", entrance to the Crypt)
Deathly Scarabs. Easily found all around you as you zone in, non-aggro but has double up arrows and plenty of HP, bring friends.
Forsaken Shrillers are also all around you on the spiral stairs as you zone in, these mobs aggro and are very tough casters with double up arrows, have backup. Your journal should update after killing about 10 of these.
Restless Corpses spawn occasionally on the stairs but are found in more abundance inside the tunnel. At the end going right or left will end up taking you to the same room with sarcophigi, containing plenty of undead. Stay to the right of the tunnel if venturing in, so you don't spawn the alcove of Ire Minions on the left, they are probably out of your league at this point.

Ian's Forgetful Family - Part V

-Kill 5 Unearthed Settlers
-Kill 10 Corpse Feeders
-Kill 12 Sabertooth Looters
-Recover the sword "Bonechipper" (random drop from undead)

Reward: Trade Link Greaves- 137 AC at lvl 29, +6int, +3str, +12 health, +18 power, +118 def. vs cold, +50 def. vs poison

Takes place in Thundering Steppes.
Unearthed Settlers roam the dry riverbed just South and Southeast of the docks, should have no problem since you are equipped with track.
Corpse Feeders are crabs that mingle with the tougher skeletons in the dry riverbed just east of bridge keep. Easy kills, if you can get them away from the skeleton aggros, watch your back here.
Sabertooth Looters inhabit the camps in the large crater near the zone to Antonica. Easy find.
Bonechipper is dropped from random undead in the dry riverbed, should not be a problem to find if you are killing the skeletons you find along with the Corpse Feeders. Zombies in the riverbed have a chance of dropping the sword too. It is not an actual item, but will update your quest log. You could kill anywhere from 10 to 50 undead before recieving the drop, I've heard many different accounts.

Ian's Forgetful Family - Part VI

-Kill 15 Steelhoof Hunters
-Kill 10 Skeletal Troopers
-Kill named giant Ott Stompgut

Reward: Trade Link Chainmail (Tunic) - 236 AC at lvl 30, +6 Agi , +3 Str, +15 Health, +17 Power, +67 def. vs disease, +101 def. vs magic

Takes place in Thundering Steppes.
Steelhoof Hunters can be killed with most effieciency at the Centaur Bridge area, its the second bridge over the dry riverbed, going South, with Bridge Keep being the first. Fairly quick respawn here but I encourage taking an enchanter along, as there are some Centaur groups here near the bridge.
Skeletal Troopers can be found around the entrance to the Ruins of Varsoon, South of Qeynos tower 3. Travel South from the tower past some craters until you see a forest of broken trees, you should find some Troopers here.
Ott Stompgut is a spawned mob, he does not exist on his own. If you enter Deadview Pass with this quest, Ott will spawn and attack you. The pass is located along the East wall of mountians going North from North Bandit Camp (where Centaur Captain Duranas is). Ott has 2 trained bears with him as pets, an enchanter would do wonders in this situation as well.