First, let me extend a welcome to the forum!
Posting a wanted ad...
First make sure you have navigated to the classified page and not the classified discussion section of the forums. (Yup... confusing!) Click the "Classified" tab at the very top of the page or go to the Marketplace forum section and look for the small link that says "Post your ads here (click)." Either one should take you to a page that looks different (with a different URL).
After you get there, click the button to post an ad. You will have to log in again (same credentials as here). Then you can follow the instructions to create your ad. It might be helpful to mention your size and/or weight
Once you create the ad on the classified page, it will automatically generate a discussion thread in the Marketplace forum, where people can ask questions. Sellers may send you private messages as a way to exchange contact information. The forums and the classifieds have separate messaging systems, so you'll need to monitor both.
Another option, if you haven't found it already, is to post on www.fiberglass-rv-4sale.com
Best wishes in your "egg hunt"!