Investing in the Monk class is a labor of love. You can only buy it through a VIP account or on the DDO Store.
And once you have it, you might find it more complex than you realized.
Years ago I found myself in this fix and decided to record what I learned and what others taught me. The result was "The Book of Syncletica," named after my first Monk.
And now, as I work on an updated version of the guide, there's now a place where you can play with me and others to get some training on your character.
The Syncletican Monastery, only on the Ghallanda server, is offering new Monks or those that like to play them a space in the dojo to learn and enjoy.
The early rules (aside from courtesy, fun, and keeping real-life out of the game whenever possible), is that your character must have at least 3 Monk levels and be Lawful unless you are adding support classes (Rogues, Clerics) a mage, or special Monk-supported multiclassed characters. (Naturally, no pure Fighters or Barbarians).
To submit an application, visit https://syncleticanmonastery.shivtr.com/. Enlightenment is coming.
(Update: June 2021: We're still small but going! We'd love new members who are new to Monks or love some company. I am most active doing evenings and Sundays, US Eastern time, but there are several onboard happy to help!)