Railworks America

I had recently reinstalled TS2013 due to me getting a new Dell PC,Odd thing is what happen too my Routes I had?I had the CSX Mainline,PL&E,Tennsesse Pass,NS Atlanta.And some other Routes installed too.So why are these Routes not in the Routes list?Anyway I can get those back without reinstalling them again?

Those routes, and any DLC that was not bought on Steam, must be reinstalled manually.
Quickest way is probably to copy the entire railworks folder from old computer to new computer.

What if I did a verify Cache would that help?

UPSD70ACe wrote:What if I did a verify Cache would that help?

It wouldn't help as these are 3rd party routes ie not RSC routes.
You'll need to reinstall your 3rd party content.

What will happen if I did the Verify Cache? Will I loose all the Routes add ons I had bought & installed from RSC?

No.
It verifies files that were downloaded from Steam only.
More precisely, it has a list of default files and their checksums and goes down the list.
If any of these files is missing or has changed, then it will download it again from Steam.
3rd-party content such as routes and scenarios is invisible to this process because those files are not on the list.

The only things that you could lose are modifications that you made to default files.
For example, if you applied simer4's sound pack for the default SD40-2, a verify cache will reverse the change and you will have to reapply the pack.

Then I will just have to download/install the CSX Mainline,NS Atlanta,Soldier Summit etc again.

NS Atlanta is not available at the moment.
It might be easier to transfer it from your old computer.