Is there a way to use the iSpeech SDK for iPhone in my monotouch project? http://www.ispeech.org/developers/iphone
This looks like an ObjectiveC library. The way to use this inside a MonoTouch project is to create .NET bindings for the library.
There's one reference of this already? existing in their forums but I could not google it. You might want to ask them (iSpeech) if they are aware of it before starting your own bindings.