Your OB paid such close attention to your hypoT was more for your child's benefit than yours. Babies born to untreated hypo mothers face a much greater risk of low IQ and other health effects than those with healthy mothers, but low thyroid also contributes to pre-eclampsia and miscarriage, as well.
1. Where can I find more info on hypothyroidism?
My favorite site to recommend is UC-Davis'. HypoT is explained in complete and clear language. (My only objection to the information there is that they only include info about synthetic T4 meds, not mentioning the usefulness of natural dessicated thyroid.) ~
The Thyroid Australia site is extremely informative... I recommend it too.
An extremely useful book on hypoT treatment is Solved: The Riddle of Illness
by Dr. Stephen Langer. It offers real hope to people having trouble getting diagnosed, or for those millions who continue to be undertreated due to doctors' ignorance.
Another good book ~ What Your Doctor May Not Tell You About Hypothyroidism
by Dr. Kenneth Blanchard.
2. What kind of doctor is best for treating this disease?
The best kind is any kind who knows something about thyroid disease. There have been people here who had a knowledgeable OB-GYN, or GP, or internist, or naturopath, or osteopath, or endo. You'd think an endo would be the logical choice, since they specialize in the glandular system; but they too frequently specialize in diabetes and know little about thyroid. They also tend to treat by the textbook, and hypoT is not a disease that can be treated strictly that way.... So quite a few of us have not had the best experience with this speciality.
Ignorance about thyroid disease abounds in the medical community. It takes a flexible, experienced doctor who knows how best to work with a knowledgeable patient to treat it successfully. More of them "don't know what they don't know" than any of us would like to think.
Holistic-minded doctors usually have the best success at restoring the hypo patient's health. Doctors of osteopathy (DOs) are typically holistic-minded, and for some patients, they are best.
3. What are normal levels for thyroid function?
Ninety-five percent of healthy people with no signs or symptoms of thyroid disease have TSH of between 1 and 2. The Amer'n Acad. of Clinical Endo's says that a TSH of 2.5 plus symptoms warrants a trial of thyroid replacement. But for people already in treatment, TSH means little. For many people, TSH must be totally suppressed or very below-range before they feel well.
The levels that matter most are the free T4 and free T3. These must be well in the upper part of the lab's range in order for people to be free of the signs of thyroid deficiency, and to feel well.
You're quite right that this can be a serious disease. Un- or undertreated hypoT leads to heart disease, osteoporosis, and serious mental dysfunction. It wreaks havoc on fertility and the ability to carry a baby to term. It can shorten life and create serious health consequences, so you're right to want to know more about what it can mean to you.