You could list it here. I’d also try the Samba classifieds–they have a section for “other VW-related” where kit cars like ours can be found.
http://www.thesamba.com/vw/classifieds/
Craigslist is where I bought mine–free listings with pics. Easy to use and lots of action.
Then there’s always ebay.
Make sure you take lots of pics and post all the information you can about the car–mileage, year of the donor car and engine, any new or recent parts, anything that’s needed or missing–everything you can think of.
These VW-based cars tend to go for anywhere from about $2500 of a well-used one to maybe $5500 or more for a really fine example.
Good luck!