A Quick Note
Note - This guide covers only the Book 3 Epic Quest and does not cover the North Down quests (i.e. you do not need the North Downs Quest Pack to follow this guide). North Downs is not an area I quested in as there is heavy overlap in level ranges with the free Lone Lands zone (20-30) and the higher end of the zone does not offer enough content to get from 30-40 making Evendim a better choice.If you followed my Lone Lands guide you have already done the Foreword stage below so start at Book 3: The North Downs.
Foreword: The Lone Lands
1. Head into the Lone Lands (west of Bree Land) and follow the great east road (east) across the map to the city of Ost Guruth (31.5, 29.5)
3. Exit to the south and ride west to Candaith's encampment at (30.2, 37.9). Speak to Candaith to continue B3:FW.
4. Use your milestone to return to Ost Guruth, speak to Friedrich and complete Trouble at Trestlebridge. This will give you a free teleport to the North Downs.
5. Speak to Guardsman Otley to turn in in Bree-Town to Trestlebridge if you have it
Maria Shelton (17.5,54.0) Guardsman Otley (17.4,53.9) (also Talbot Hinton (17.3,53.9) Elsie Woodruff (17.3,53.8)
6. Find the Stable master Hal Fincham (18.0,53.6) and purchase a ride to Esteldin
Book 3: The North Downs1. At Esteldin enter Halbarad's Study(9.4,41.2) and speak to Halbarad to finish B3:FW. Accept  B3C1: Ranger of the Fields
2.Return to the Stable Master and purchase a ride to Trestlebridge. Jump off when you reach the Greenway cross-roads (13.4,54.7) and ride north-west to Mincham's Camp (13.1,55.3)
3. Speak to Mincham and turn in B3C1. Accept B3C2: The Gates of Fornost. Ride north to the Norbury Gates and kill 10 Orcs and 10 Wargs (level 32 mobs) outside the gates. Return to Mincham's camp and turn in B3C2
4.Accept B3C3: Fallen Once More and ride west to Esteldin (either ride all the way there or ride to nearby Amon Raith (12.8,52.5) and buy a stable ride). Return to Halbarad and turn in B3C3. Accept  B3C4: A Call to Dwarves, B3C5:A CAll to Elves and B3C6:A Call to Men.
5. Exit Esteldin and follow the road north to Orthrikar. Speak to Hannar (7.2,44.9) and turn in B3C4. Accept B3C4(2): Freeing Dori. Exit the city and ride west and enter Ost Galumar (7.0,46.9). Work your way through the ruins until you find a cage (7.6,47.0). Open the cage to find Dori and escort him to safety (mostly lvl 30 mobs with a few lvl 35 elite mobs)
6. When Dori says he's can make it on his own return to Orthrikar and speak to Hannar to complete B3C4(2). Accept B3C4(3): The Dwarves Shall Come.
7.Exit Orthrikar and ride south, past Esteldin, to the elven city of Lin Giliath. Enter Tham Giliath (13.7,44.9) and speak to Gildor Inglorion to finish B3C5(1). Accept B3C5(2):Tending the Glade
8. Ride south east and ride through the Eastern Pass (14.6,45.8) to a small clearing (17.4,47.0) which "looks to be a good place to draw upon the Elf-stone's power". Use the Elf-stone and continue south then east until you find Drukordh (level 35 Elite-master) (18.9,46.6). Kill him then return to Lin Giliath and speak to Gilidor to turn in B3C5(2) and accept B3C5(3): Might of the Elves.
9. Speak to Dilath, the Stable Master, to buy a ride to Esteledin and then speak to Arochon , the Stable Master, to buy a ride to Trestlebridge.
10. Head to Nellie Boskins' House (17.7,53.9) and speak to Nellie to complete B3C6(1). Return to Hal Fincham, the Stable Master, and buy a ride back to Esteldin
11. Talk to Halbarad to complete B3C4, B3C5 and B3C6(2). Accept B3C6(3): The Defence of Trestlebridge. Speak to Halbarad again to travel to the instance and at the end to exit.
12. You return to Nellie's house in Trestlebridge, speak to Nellie to finish B3C6(2) and accept B3C6(3): The Free peoples of Trestlebridge. Speak to Hal Fincham, the Stable Master, and buy a ride back to Esteldin.
13. Speak to Halbarad and turn in B3C6(3). Accept B3C7:The Council Assembled.
For efficient levelling it's best not to finish the quest now as the last part requires a trek to Rivendell. I'll give instructions below for the sake of completeness but I highly recommend leaving the final turn in of Book 3 until you reach level 39 - at this point you need to visit Rivendell anyway to start work on your Legendaries so it makes sense to combine the trips.
If you are happy to leave the final turn in until later then you should speak to Arochon the stable master and purchase a ride back to Tinnudir where you can continue questing in Evendim.
Finishing Up: Rivendell (Trollshaws)Travel to Rivendell. Assuming you don't have swift travel I would recommend you take the stable routes as far as you can (Esteldin -> Trestlebridge -> West Bree run to East Bree -> The Forsaken Inn -> Ost Guruth) and then ride east into Trollshaws, follow the road east to the Ford of Bruinen and then climb the mountain and bear north until you pass through The Gates of Imladris (32.1,6.2) and enter Rivendell.
If you have a house you can make the trip shorter by using your Travel to Personal House skill and then free-swift travel to West-Bree. If you have any of the rep 'Travel To' skills that would also make the trip shorter. If you have already visited Rivendell you can take a further Stable route from Ost Guruth to go directly there.
Once in Rivendell go to the Guest Rooms (30.7,6.2) and speak to Aragorn. Turn in B3C7 to complete Book 3.