Write Linux Device Driver

Hello Friends,
Hi Myself Naresh (B.E. Comp. Eng) from Mumbai…

I’m a Linux Device Driver Writer…
I would like to learn writing Driver of “USB Devices”…BUT
before that I’m presently working on “PCI ETHERNET NETWORK ADAPTER (RTL8139)” for that – reading it’s Datasheet and trying to write simple backbone Driver BUT for that friend I need your Help…

Resources I have/using –
1. Few Online Documents….
2. Regular Reader of LinuxForU Magazine…
3. Linux Device Driver (Online Book) by RUBINI

Plz share some knowledge/docs/samples u have….

Thanks in advance…
Naresh