So quite a few of us have or are constructing EDH decks, and so I thought I'd direct interested parties to the rules and reprint here the rules and current banned list
Rules Site
http://www.dragonhighlander.net/rules.php?PRINT=1--Taken From The Above Website
EDH is designed to promote social interaction.
It is founded (and dependant) on a social contract, otherwise known as a gentleman's agreement. Unsporting conduct (whether extreme or simply "being a jerk") should not be tolerated by players. Refusing to play with antisocial persons is the fastest way to better EDH community.
However, because players have varied opinions of what constitutes fair and/or fun play, a recommended banned list is maintained to help guide players towards a good social experience. House rules or "fair play" exceptions are always encouraged if they result in more fun for the local community.
If you want to enjoy the type of games you've heard associated with EDH, avoid cards like these:
Ancestral Recall
Balance
Biorhythm
Black Lotus
Coalition Victory
Fastbond
Gifts Ungiven
Kokusho, the Evening Star
Karakas
Library of Alexandria
Limited Resources
Lion's Eye Diamond
Tolarian Academy
Channel
Metalworker
Mox Sapphire, Ruby, Pearl, Emerald and Jet
Panoptic Mirror
Protean Hulk
Recurring Nightmare
Sway of the Stars
Time Vault
Time Walk
Tinker
Upheaval
Worldgorger Dragon
Yawgmoth's Bargain
Painter's Servant
Staff of Domination
Additionally the following legends should not be used as a General:
Braids, Cabal Minion (Effective 2009-06-20)
Rofellos, Llanowar Emissary (Effective 2010-06-20)
Deck Construction Rules
Players must choose a legendary creature as the "General" for their deck.
The General's mana cost defines what colour of mana symbols may appear on cards in the deck.
Coloured mana symbols which may appear in an EDH deck are restricted to the colours appearing in the General's mana cost.
Lands whose type includes swamp, island, plains, forest and/or mountain (e.g.: basic lands, shocklands, dual lands, Shadowmoor special-basics, etc) DO contain the corresponding mana symbol(s) as per CR 305.6. As such, they may not appear in a deck unless the General is of the corresponding colour(s).
While Hybrid mana symbols may be played with either colour mana, they count as both colours. As such, they may only be played with a general which is ALL of the hybrid mana symbols' colours.
Basic land words (swamp, forest, etc) in the text box of a card do NOT represent a coloured mana symbol. They are not restricted to generals of the same colour.
A deck may not generate mana outside its colours. If an effect would generate mana of an illegal colour, it generates colourless mana instead.
An EDH deck must contain exactly 100 cards, including the General.
With the exception of basic lands, no two cards in the deck may have the same english name.
EDH is played with vintage legal cards, with two exceptions:
cards are legal as of their set's prerelease
Shahrazad is legal for play in EDH
Play rules
The start of game procedure for EDH is as follows:
Players announce their choice of General and move that card to the command zone.
Players may then sideboard if the optional rules for sideboards are being used.
Each player draws a hand of seven cards.
Players may mulligan, using the modified "Partial Paris" method.
Partial Paris Mulligan rule
Because EDH games are long and usually not played in multigame matches, EDH uses a modified mulligan rule designed to aleviate mana-light hands without significantly increasing the odds of finding individual cards. This is also known as the "Brittany" mulligan rule.
In turn order, players may exile (face down) some or all of the cards in their hand.
Each player then draws one less card from their deck than the number they exiled.
Players who exiled at least one card may return to step 1 and repeat the process, drawing one less card each time.
Players shuffle all exiled cards into their deck.
It is worth noting that even with this form of mulligan, decks playing an insufficient number of mana sources will routinely draw poor hands or insufficient mana as the game progresses.
Being a General is not a characteristic[MTG CR109.3], it is a property of the card. As such, "Generalness" cannot be copied or overwritten by continuous effects, and does not change with control of the card. Examples
If a player has been dealt 21 points of combat damage by a particular General during the game, that player loses a game. Details
This is an additional state based effect.
General Damage is cummulative throughout the game; nothing can reduce the amount of damage a General has previously done to a player.
Because it is a property of the card and not a characteristic of the game object, a card is still the same General even if it leaves the field and returns.
While effects can raise a player's life total, it doesn't reduce the amount of damage previously taken from a General. (eg: Beacon of Immortality)
Conversely, combat damage can be reduced, prevented, or replaced as it is taken, in which case it was never dealt and doesn't count towards the total taken from that General. (eg: Fog or Captain's Maneuver)
General Damage is specific to each General/Player pairing, not combined across all Generals.
A player can lose if he or she is dealt 21 points of combat damage by his or her own General (ie: under someone else's control).
While a General is in the command zone, it may be cast. As an additional cost to cast a General from the command zone, its owner must pay {2} for each time it was previously cast from the command zone. (ie: it costs 6WW to cast for the third time.) Details
If a General would be put into a graveyard or exile from anywhere, its owner may choose to move it to the command zone instead. Details
This is a replacement effect; the creature never goes to the graveyard and will not trigger such abilities.
Generals will move to the library or hand as normal; only transitions to Exile or the Graveyard may be replaced.
Players begin the game with 40 life.
Generals are subject to the Legend rule; they will be put into the graveyard or command zone at the same time as any other Legendary creatures with the same name.
New: Abilities which refer to other cards owned outside the game (Wishes, Spawnsire, Research, Ring of Ma'ruf) do not function in EDH unless the optional sideboard rule is in use. If sideboards are used, wishes and similar cards may retrieve sideboard cards.
So for TL;DR
Choose a Legendary creature to act as your general
Your deck may only contain mana symbols which appear in your General's mana cost (any where on the cards. Hybrid cards may only be used if both colours appear in your general)
You have 100 cards in your deck including the General
Aside from basic lands no 2 cards may have the same English name
Players start with 40 life
Generals are placed in the command zone
Generals may be played from the Command zone
Each time beyond the first the general costs an extra 2
If the general would be placed into the Exiled zone or the graveyard you may move it to the command zone as a replacement.
If you take more than 21 combat damage from a particular general you lose.
House Rules:
So I guess we've not really come up with any real house rules for EDH but some groups have.
Though I think we have a few things that are frowned upon.
Mainly anything that sets a players life total to a particular number such as Sorin Markov's 2nd ability or Magister Sphinx
If anyone has other suggestions for house rules or other advise etc feel free to comment.