In the world of Large Scale trains there are several train shows each year where you can meet with other people in the hobby, take seminars, go on layout tours and view and buy from the large number of vendors who display their merchandise at these shows.

There are four major train shows in the United States focusing on Large Scale. The first each year is the Southeast Large Scale Train Show(SELSTS) held in Perry, Georgia in mid-February. The SELSTS was first held in 2006 and the show is focused on hobbyists in the Southeast parts of the United States. The 2007 show had no layout tours but attracted a large number of hobbyists. It is open on Friday and Saturday at the Georgia National Fair Grounds in a large convention hall. http://www.largescaletrainshows.com/cat_index_21.html

The second show held each year is the East Coast Large Scale Train Show (ECLSTS) held in York, Pennsylvania in late March. This is the largest of the shows and draws a large number of hobbyists and venders. It is in its eleventh year and has not had layout tours in several years. It is open in a very large convention hall on Friday and Saturday at the York fairgrounds.
http://www.largescaletrainshows.com/index.html

The third show each year is the Big Train Show that was held for years on the Queen Mary in Long Beach, California. In 2007, the show moved to Ontario, California and attracted a large number of visitors.

It is a four-day show, with bus tours of several garden railroads on Thursday and Friday. Saturday and Sunday feature clinics and an exhibit hall with many vendors and modular layouts.
http://www.bigtrainshow.com/

The forth show is the National Garden Railway Convention held each year in a different city. For 2008, the show will be held in Chandler, Arizona, at the San Marcos Golf Resort. The convention runs from Wednesday through Sunday. Layout tours will be open from Monday through Sunday in Phoenix, Tucson and Arizona City. The vendor hall will be open for some hours on Wednesday through Sunday and clinics will be given on Wednesday, Thursday and Saturday. Although the show is called the National show, it is sponsored by individual Large Scale clubs throughout the country and there is no central organization involved.
http://www.ngrc2008.org/

Other smaller shows include a show put on by EagleWings Ironcrafters in mid-April in Phoenix, Arizona, at the EagleWings company location. It is an open house and features many of the local vendors. It is a Saturday and Sunday event with layout tours of nearby Garden Railroads.
http://eaglewingsironcraft.com/upcoming_events.php

A final annual convention that attracts many Large Scale hobbyists is the National Narrow Gauge Convention held in Portland, Maine in late-August 2007. It is in a different location each year and will be held in Portland, Oregon, in 2008. The show runs from Wednesday to Saturday and features layout tours, modular layouts and a vendor hall. This convention is for all scales, but includes Large Scale.
http://www.27thnarrowgaugeconvention.net/