You can start using it here immediately, or you can integrate it into your own website.
Take a look at the demo page for other examples of how Converse.js can be configured and used.
No problem! With converse.js you can register an account on any public XMPP server that allows registration.
I'm available for paid-for features, custom development and consulting.
However, please don't contact me personally for free support, use the other channels mentioned above. Here's my contact form.