My favorite one is Walthers, they have most every thing i want. I have bought some stuff from a few others, i.e. internet trains, and a few off ebay too. Also bought some detail stuff from microscale.com for customizing soem of my truck fleets.
check out this guy. http://www.bonanzle.com/booths/jsgeare :thumbsup:
I have bought alot of my rolling stock from him. GREAT prices.
and FREE shipping to boot !!!! look for his Athearn RTR stock and his Athearn blue box kits.talk about great prices