Where to ask for copyrights?

[Dr. Beckenstein]

I am working on a website with a few adventures I have written. Among them are a few for Gurps Traveller.

Before I put them online, I wanted to check it with the copyright holders if it is okay to put self-written stuff online. Steve Jackson Games is cool with it, as long as I stick to their guidelines .

But who (or where) should I ask for Traveller in general?

And has somebody here any experience with something like this?