In the US, the largest wholesale fine jewelry show is held every June in Las Vegas, Nevada. It's held at the Sands Convention Center and takes at least two days to view. Every major retailer of jewelry attends this show. The show is very strict on admissionand a retailer must have proof of a commercial location to attend. I have personally seen them turn away buyers who flew in from Europe without the proper paperwork. The admission requirements can be found at:
www.jckgroup.com

The JA is another major fine jewelry trade show held in New York.
www.ja-newyork.com

There are many trade publications for fine jewelry, but the two I would start with are:

Jeweler's Circular Keystone

National Jeweler