Susan,
Thank you for agreeing with what my massage therapy instructor told us constantly. Word of mouth is your best client builder. If the people you take care of are happy, they will take care of you both monetarily and with new clients.
Yes, professional business cards are the way to go. Don't leave them in the box they came in. They will do no one any good there, collecting dust. Always have some in your purse, pocket, and vehicle and share them everyday!