what should I "raed carefully before advise anything"?
You ask about PIC&USB. I gave you link to this page:
**broken link removed**
At the end of that page you have link to this site:
**broken link removed** and their project:
SmartMedia Flash USB Reader / Writer with PIC18F872 o SX28. Source and schematic are here:
**broken link removed**
**broken link removed**
What else could you need about PIC&USB, what I didn't give you?
On this page I found similar example with another USB chip: Philip's PDIUSBD11 instead FTDI's FT8U245AM.
**broken link removed**
But, maybe you like this example more than first one.