Dave,
I found a Asian site that has a lot of nice detail parts, but, they are for 1/12th scale stuff and mostly for antique bikes. The stuff is awesome and the work I saw on these sites make me embarrassed to even think of posting anything I have ever done in my life. These guys do some of the best work I have ever seen bar none. They are relacing all the spokes on their wheels, making new wheels and hubs, stacking PE parts to make their engine jugs, making working chains link by link and that's just the start. It was hard to tell which was a model and which was the real thing. They do like to weather their stuff, and with me doing military until now, that is right up my alley. They have all of their marbles in one bag for sure. Here's a link to one of the sites for some detail parts. Check it out and click on some links and surf around looking at the work. It's all in stick letters, but pictures are in our language. :-) I'll learn a lot from looking at how they did things, just wish I could read that stuff to learn more.
Ted
edit: forgot the link: http://www.cosmos-factory.com/shop/index.html