If your opening up a thread for your service then you should provide some of your samples in your thread itself for the potential buyers to check. Don't expect people to contact you for the samples because a lot of people are there to provide these services.
Also, you can list your gigs on fiverr site because there this segment got a lot of demand. I too sell some of the intro videos on fiverr and receive few orders every month.
Thanks for the tips mat. Kinda new to this world and I clearly need all the help I can get.