Hey Mark,

pretty much seems like the google translator is quite handy for this. Check this out:
Translated Marketplace

On the very bottom you will find a link for "ad". Normally it works like this: If you like to sell a larger amount of parts commercially, write a brief mail to our webmaster Maik Fassbender, he gives you a bank account or perhaps a paypal address or something for making a donation, a few bucks. Just a small amount of items for sale or searching for a specific item is for free. However you fill in the form accessed through the ad button, and it will be (i guess) posted manually into the marketplace by Maik.

Could be that this takes a day or two, but you can rely on Maik, he's gonna drop you a line, when its done.

Good luck

Flo

- Menschenskinder! 8 Zylinder!? -