I’ll share my experience when I first offered ghostwriting services. I’ll even show you the specific sales pitch I used. What I did was launch a Warrior Special Offer (WSO) over at the Warrior forum. If you’re not a member at this community yet, you can join for free. To post a special offer, you pay $20 through an automated system, and your offer shows in the market place for approximately 3-4 weeks.
Another site, WarriorPlus, archives past Warrior Special Offers. This is great, because I can show you exactly what my offer looked like, plus you can read any replies etc.