Do you want to write Device Driver under linux? What's the easyest way to do that...I have searched couple of time in net to get any device driver kit[ ofcource free] where everything sould be configured and preloaded. You need not to worry about any setup to code for your new device driver. I got one like windriver from Jungo but it is propitary.I don't have money to pay. So i stopped when Gregkh released first LDDK with 2.6.16.18 kernel and full LDD3 book.
You could visit his home page.
If you want to get full iso image then visit this site