Doulas (also called childbirth assistants) are specially trained to provide support during labor and delivery. A doula also serves as a go-between for the doctor, nurses, and you and your mate. Think of her as a knowledgeable companion who can offer encouragement and wisdom throughout the birth process. Experienced doulas know all about positioning, soothing touch and other comfort measures to ease the general experience.
Many doulas also offer at-home help after baby is born, usually for a couple of weeks. Her role is to mother the mother (you), and may change from day to day. She'll generally do whatever is necessary to help you adjust, including making sure you’re well-fed and hydrated. She will also provide education for you about baby care and breastfeeding. To find a doula, ask your doc for a recommendation or try the Doula Organization of North America's finder.