Dragonmark feats in 4th Edition provide characters with the ability to master and perform certain rituals. The feats refer to rituals of a certain category or to specific rituals listed in either Player's Handbook or Eberron Player's Guide. This makes sense, because those are the only two books that are required to play an Eberron character.

Here are additional rituals from other sources that I believe should be tied to those feats:

Detection:
No additions. The feat pertains to all divination rituals.

Finding:
Clear the Path (Forgotten Realms Player's Guide)
Detect Treasure (Arcane Power)
Dowsing Rod (Primal Power)

Handling:
Animal Friendship (Player's Handbook 2)
Beast Growth (Arcane Power)
Bloom (Player's Handbook 2)
Call Wilderness Guide (Player's Handbook 2)
Raise Beast Companion* (Martial Power)
Reduce Beast (Dragon Magazine #405)
Speak with Nature (Player's Handbook 2)

Healing:
None, except perhaps Purge Spellplague, which isn't an Eberron plot point.

Hospitality:
Affect Normal Fire (Player's Handbook 2)
Create Campsite (Player's Handbook 2)
Preserve Flame (Arcane Power)
Rope Trick (Hospitality)

Making:
Shatter (Dragon Magazine #405)
Shatter Bonds (Dragon Magazine #405)
Stone Shape (Dragon Magazine #405)
(These are Exploration, but seem to pertain very much to creation. I'd also think Tenser's Floating Disk would be a good Making ability, but it was left off.)

Passage:
Passwall (Player's Handbook, not sure why this wouldn't be theirs.)
Easy Passage (Draconomicon: Chromatic Dragons)
(It's an exploration ritual, but it has "passage" right in the name.)
Trailblaze (Forgotten Realms Player's Guide)

Scribing:
None. They can already master and perform all rituals.

Sentinel:
Mark of Justice (Divine Power)
Primal Prison (Primal Power)
Sentinel Eye (Draconomicon: Chromatic Dragons)
Skull Watch (Open Grave)
Wyvern Watch (Player's Handbook 2)

Shadow:
Change Self (Dragon Magazine #405)
Hallucinatory Terrain (Dragon Magazine #405)
Silent Image (Dragon Magazine #405)
(Arguably Shadow Bridge and Shadow Walk, except that the mark doesn't seem connected to the Shadowfell in any way.)

Storm:
Control Weather (Player's Handbook 2)
Lower Water (Arcane Power)
Portend Weather (Primal Power)

*Raise Beast Companion is automatic for beastmaster rangers (and not really useful for anyone but them) and technically available to the Mark of Healing, being a Restoration ritual.)