Since I still observing people keep doing EN DA I feel like this topic is needed.
First, when you are doing your epic life up to 30 you'll probably get enough tokens (20 to 45 average) to TR. So usually you need extra tokens only if you are new player and dont wanna run epic content yet; scrub that farming heroic lifes only; want to buy those awesome augments in the 12. Anyway, if and when you farm it you wanna do it fastest and less boring way possible. There are variants:

Devil assault epic normal.
Lasting: 25 to 35 mins depending on group. 25 kinda minimum.
Token amount: 1-2 per person per run, very random, but looks like 1,5 on average.
Free to play: no
Difficulty: decent to very easy, depending on toon. Most firstlifers can solo it with hireling.
Full party min per token: 3.33. To get 20 tokens you'll need 2 to 3 runs with full party when everyone passing them to you. So around hour or 1.5 hours.

Lords of dust epic elite.
Lasting: 7 to 10 mins. May be even faster with lvl 30 folks.
Token amount: 1 per person per run.
Free to play: yes
Difficulty: hard to easy, depending on group, most forstlifers cant solo it. A single high level dps or spellcaster can dramatically speed it up though.
Full party min per token: 1.41. Nuff said with some high levels in a party this number can be less than 1 with superfast completions. Need 4 runs to get 20 tokens. Around 35 mins.

The chamber of Raiyum (aka Wizard-King) epic elite.
Lasting: 5 mins with 3 lvl 30 guys. 20 to 40 mins otherwise.
Token amount: 2 per person per run.
Free to play: no.
Difficulty: extremely hard to decent without high levels in a party, trivial with 3 lvl 30 guys: rest 3 members should just wait at chest room. Not possible for most firstlfsers solo.
Full party min per token: 0.41 if carried by high-levels, 2.5 if not and in a decent group. Need 2 runs of it to get 20 tokens.

So if you have some lvl 30 friends you may have your 20 tokens in literally 10 mins. I. DA you usually offer people to pike and get free xp/seeds/loot for their tokens, but this quest is slow and boring as fuck. I'm pretty sure you can find some folks in any server who will join your lod or wizzy runs. Another option is to join some daylies, low level epic raids (adq, von, chrono) and ask folks to pass tokens, yet this is very random method, cause most people prefer to keep their tokens while leveling.

Partycrashers and The Snitch are also pretty good sources of Tokens if you know what you’re prepared.

Post an LFM for XP Dailies(von3, Wizard King, Two Toed Tobias, Spies in the House, etc) and include in the description "Looking for Tokens" then casually ask in party. These groups will always fill and you're likely to get someone who's just grinding out epic experience and happy to pass you theirs. Really the main secret is to just ask; if you don't say anything no one will have any idea.

BOB - 2 mins per run