Just some sites that are worth looking at
http://roundhouse-eng.com
http://accucraft.co.uk
http://pps-steam-models.co.uk/
http://www.freewebs.com/mhlr/
http://www.freewebs.com/shrailway/
http://www.freewebs.com/wlrail
http://www.gardenrails.tk/