I'm guessing you are fairly new to the community, so I'm going to elaborate a little on what he is saying. There is a lot of effort put into making tracks and even painting cars, so the people that do those things (in their free time, no less) aren't going to spend all of their time making tracks and carsets that someone else wants, they are going to work on what they want. I'm not saying don't ask, I'm just saying don't expect to be flooded with approval from people that are going to make those things for you. It also is probably not a good idea to be consistently asking for stuff. If you want these things, you should learn how to work on them yourself. People are much more responsive to "I'm trying to make a track but I can't figure out how to do X" rather than "please make this track for me."