How can I develop a driver to use the phone as an host for a usb device

Hi all, I want to develop a usb driver for Nokia N8.
The phone should will be the host device.

Where can I find support to do this?

I would assume that to be really difficult nowadays. Basically public SDKs are not supporting that kind of development, and there are not really too much you could get addition to it. Thus unless you have really great business case, I would suggest you look into other platforms for develpoing the solution for.

You can certainly read the book in the Wiki, [url]http://www.developer.nokia.com/Community/Wiki/Symbian_OS_Internals[/url], it is somewhat "karma" thing that USB is discussed in chapter [I]13[/I]. It does not seem to be over-discussed in fact. An other thing you can refer to is checking the ex-open source Symbian^3 code (symbiandump project on SourceForge).
However neither of these sources will contain hardware-related details about any Nokia device, including the N8. Also, installing device drivers is not necessarily possible at all, and even if it is possible, it certainly needs signing from Nokia, including (presumably) all capabilities, and perhaps other checks as well.
You can of course experiment with Technical Support, but in general I would not bet on that a 3rd party developer can squeeze out such information from Nokia, now, at the end of 2012.