Good questions.
First--there are doctors out there who will prescribe antibiotics to preppers. Don't be afraid to ask your doctor and to approach other doctors until you find someone who understands your needs. And yes, veterinary antibiotics can be used as well.
I'm going to provide you with several links here.
Have a look at this 10-minute video, "Top 5 Antibiotics for SHTF Storage":
http://www.youtube.com/watch?v=DOfth...eature=related
I find that Survivalblog, by Jim Rawles, is often an excellent resource. In this case, after reading your question, I was reminded of a few posts that would interest you ...
Seven Antibiotics to Stockpile and Why, by C. Koelker, M.D.:
http://www.survivalblog.com/2011/02/...stockpile.html
Herbal Medicine for Preppers:
http://www.survivalblog.com/2011/03/...reppers_b.html
A Surgeon's Advice to Preppers:
http://www.survivalblog.com/2011/03/..._preppers.html
A Doctor's View of TEOTWAWKI:
http://www.survivalblog.com/2010/12/...twawki_by.html
As for a medical reference book--The Merck Manual of Diagnosis and Therapy is a must have:
http://www.amazon.com/gp/product/091...SIN=0911910182
Another must have book, "Where There is No Doctor":
http://www.amazon.com/gp/product/094...SIN=0942364155
Also, "When There is No Doctor":
http://store.prepared.pro/when-there...-doyle-md.aspx