There are a number of Avengaea-themed sites and locations that invite and encourage participation. Mainly, this takes the form of interactive storywriting and art, but there are always chances to branch out into roleplay and other manners of taking part in this fantastical world. Check out the current websites offering interaction on Avengaea:
The City of Sanctuary
The Asandus capital, called Sanctuary, is located in the northern-central Novinitu mountain range. It is a central locus for Asandus culture, and talk of politics and pomp, as well as a great deal of luxury amd wealth, all make up vital aspects of the city. It is set in and around a mountainside, delving deep into the earth below, and is always expanding. In this city is located the Avengaean Bonding Complex, the only place on Avengaea where the unconventional practice of bonding asandae takes place.
Available at Sanctuary:
The Avengaean Nidus is a very new construction, created by a number of part-Asandae who were born offworld and immigrated to the planet. It is intended to house offworld dragons and the like who want to live on the small planet, and is so far the only place on Avengaea where public flights and public hatchings are run. It has a growing reputation as a good place of business, and its Alas, or organizations of dragons, provide a number of services to the surrounding areas.
Available at Nidus Avengaea:
The concept of setting up a roleplay that takes place on Avengaea has been around since the site's inception, and was actually an integral part of the world's creation in the first place. Still, the infrastructure for an actual Avengaean roleplay isn't really in place yet -- and won't be for a while. While there is a very limited possibility for roleplay at Sanctuary (under the Places heading), I fully intend to start something larger and more general up in the next year or two. For the moment, however, consider this a "watch this space".