The Gundabad Guide Series covers pretty much everything that there is about the zone. It not only gives you helpful pointers but also includes a summary of the main story.
*Legendary Progress - Overall Problems of the Three Legendary Systems
*Legendary Benefits - Bullet List of Things Removed/Changed for Legendary System
Part 1: Gundabad Preparations - Everything leading up to Gundabad, including Update 30.3.
Part 2: Gundabad Launch - Things to beware of going in and unlocking features
Part 3: Mattugard
Part 4: Deepscrave
Part 5: Stonejaws
Part 6: Car Bronach
Part 7: Missions - Provides a list of each mission and which ones you should do.
Part 8: Allegiances - Guide to where you need to go for each chapter.
Part 9: Jewels - Information on what you need to do to complete these quests.
Part 10: Gloomingtarn
Part 11: Clovengap
Part 12: Welkin-Lofts
Part 13: Dailies - Where to get Enhancement Runes and Embers of Enchantment
Part 14: Decorations - Every current decoration available and which ones you should buy
Part 15: Finale - Conclusion of Gundabad through the Epic and Instances