The first thing you want to do when reaching level cap is doing the featured instances daily, if you can. You can run 2 featured instances every day if you are at cap level, one one level 100 and one of level 105. Each run will give you a box, and if you are lucky, you will get 2-slotted essence gear from those boxes. If you complete the daily instance on level 105 T2, the fellowship will have a change of looting gear, that you can roll for.
You can trade a piece of armour for another from the same instance for your class. The cost is 1 armour pieces and 15 forgotten coins.
The featured instances change weekly, and different instances will drop different pieces of gear. Remember that gear will bind on acquire, which means that you cannot trade or sell them to other players or your other toons.
Halls of night: Head, Shoulders Inn of the Forsaken: Shoulders, Feet Ost Dunhoth: Head, Legs Ost Elendil: Gloves, Legs Sammath Gul: Chest, Gloves The Bells of Dale: Chest, Feet
2. Pelennor Gear
With update 18 and level cap being raised to 105, we got some new instances: Pelennor instances. This is where you get the level 105 4-slotted pieces. This is currently the set of gear you are recommended to have.
To get the gear, you simply need to run the Pelennor instances, and some luck to go with you. As with the featured instances, different Pelennor instances will drop different pieces.
Blood of the Black Serpent: Gloves, Legs, Feet The Quays of Harlond: Shoulders, Legs The Silent Street: Head, Chest
3. PvMP Gear
Level 105 PvMP gear is rumored to be available sometime during the summer of 2016. This has not been confirmed though, and I will update this guide with info on the new gear as soon as it is available.
The 2-slotted level 105 jewellery drops from featured instances, just live the 2-slotted level 105 gear. By completing Pelennor instances on T2, you have a chance of getting 3-slotted level 105 pocket items. All the jewellery pieces can be seen here.
T8 essences can drop from both featured instances and the new Pelennor instances. The only essenses that will drop is major, which means that crafters have to upgrade to them to greater or supreme. To upgrade them, you will need one major T8 essence, recipes for greater and supreme essences, one universal solvent per recipe, one beryl shard per recipe and a few other craft-specific materials, depending on which essence you want.
You get the recipes from the featured instance reward vendor. One greater recipe will cost 5 long lost coins and one supreme recipe will cost 15 long lost coins. Recipes are not bound, so you can buy or trade with other players, as well as send them to someone who can craft if if you cant do it on your own.