Linda,
You wrote:
>>A close friend recently suffered an early miscarriage - about a week after
her first missed period. Physically she's OK but is really shook up
emotionally..<<
I've learned through my work as a childbirth educator and through counseling
bereaved parents that a short duration of pregnancy has little to no
relationship to the depth of grief.  Think of it in terms of comforting
memories - the less memories we have of someone, the less comfort we can draw
from those memories.

>>And it happened on her birthday besides<<
So she's likely to have *anniversary grief* that is especially pronounced as
each year passes and she is reminded of the loss of her child on what is
*supposed* to be a happy day for her.

>>What book(s) would you recommend for her?<<
Some books that my students have found helpful (besides "When Pregnancy Fails"
and "Ended Beginnings: Healing Childbearing Losses" which you listed) are:

Miscarriage: A Shattered Dream (Ilse Sherokee & Linda Burns)
Miscarriage - Women Sharing From the Heart (Allen & Marks)
Motherhood After Miscarriage (Kathleen Diamond)
Empty Arms (Ilse Sherokee)
Pregnancy After a Loss (Joann O'Leary
When a Baby Dies: A Handbook for Healing and Helping ( Limbo & Wheeler)

These all deal specifically with miscarriage; there are also numerous books
dealing with perinatal loss available which I haven't included here.
Hope this is useful for her, and you.
Joyce Blangiardo RN, FACCE, IBCLC
Rockville Centre, NY