Camel have 150+ type converters in the distribution. The new Camel web console have a web page that lists them all.
And I think there is a maven tool that could generate a list of converters as well.
But the rule of thumb is that you should just try to convert to the type you want and Camel will lookup a suitable type convert if any exsits.
If not you get an exception.
The basic converters for String, byte, streams, XML should be there. There might be some odd combinations missing such as a org.w3c.Document to byte or the likes.
Keeping documentation in the wiki is time consuming and it would be much better if we get a tool to be able to slurp the javadoc in the code, then we would be able to generate a full DSL list with documentation.
As we love contributions, you can get karma to the wiki pages so you can edit and add it yourself.