It is difficult to get the ball rolling so to speak. FYI, the Craigslist deal will probably will get you a bunch of spam. As someone already stated, see if you can help a friend or co-worker who may be in need of your services.
Get yourself listed on websites. This one, Paranormalsocieties.com, ghostsofamerica, etc. Do you have a website? Use Yahoo, Google, and Bing to increase your web presence.
Remember, people are already scared by what they have going on in their home and are now asking a complete stranger to help them. Be professional! Look professional! & Act professional! There are enough fly by night so called ghost hunters.
Do your homework, research as much as you can about the field of the paranormal, read books and surf the web for reliable sites such as this one.
Don't give up! Best of luck to you!