My recommended resources for Mums-to-be and new mums:

Recommended Reading for New Parents
The Heart in the Womb
Dr Amali Lokugamage

Gentle Birth, Gentle Mothering
Ina May's Guide to Childbirth
Ina May's Guide to Breastfeeding

New Experience of Child Birth
Why Love Matters

Associations & Online Resources

The Association for Improvements in Maternity Services providing independent support and information about maternity choices for prospective and new parents.
Support and information for mothers wanting to plan a vaginal birth after previous caesarean section.
Information on homebirth in the UK.
An independent source of support and information for breastfeeding women.
Breastfeeding support from La Leche League.
Twins and multiple births association providing support for families with twins, triplets and more.
Fantastic detailed breastfeeding support and help with video clips.
Nourishing recipes for breastfeeding mums.
Online information and support for women and their partners who have experienced the loss of a baby.
Loads of useful information about UK maternity choices and statistics – find out what the caesarean rate is at your local unit!
Promoting and protecting women’s rights in childbirth.
Easier childbirth with foetal positioning. Breech and back to back babies.
A Sling Library aims to make babywearing accessible to local parents and carers, by enabling them to try out and hire slings on a short term basis.
Fathers-To-Be offers men effective preparation for fatherhood through practical education
Transforming birth experiences, through teaching men to be truly present
Non-profit organisation aiming to save lives and to end the avoidable suffering caused by inappropriate infant feeding. Baby Milk Action works within a global network to strengthen effective controls in the marketing of the baby feeding industry.
Provide information and support for those having difficulty getting sympathetic midwifery care.
Advice and  support for women with PGP (Pelvic Girdle Pain). 
Certified Professional Midwives Deborah Flowers and Ibu Robin Lim share stories and insights, information and guidance, drawing from their decades of experience in childbirth.
Midwife, Academic, Writer, Presenter. Her website Midwife Thinking has a wealth of current, well researched, up-to-date information about the physiology of pregnancy and birth and what we can all do to enhance and support that.
Midwife, Author, Researcher, Speaker. Sara has good info on the tricky tangle of GBS and much more. Well researched, current and easy to follow.
Ecstatic Hormones of Birth
Holistic Stages of Childbirth
Creative journaling to explore thoughts, feelings and experiences through pregnancy, birth and beyond for positive mental health and wellbeing
Main legal rights for pregnant employees (antenatal care includes yoga!)