For you fellow Lost Cinemaphiles, you'll find a couple of items not seen here or in my film--a rare snap of the Mini-East adult theatre, and the similarly elusive Iowa Theatre (not to be confused with its westside counterparts of the same name).
The book is part of the well-known "Images of America" series issued by Arcadia Publishing, and is available through Amazon.com (prices vary from day to day, but they're generally good), the better local book stores, and also at various East Village store outlets.
If you're especially lucky, you can catch Sarah signing copies in person and dishing tales of East Side history in her upcoming personal appearances. You should be able to find info about these here; her first signing (at the West Des Moines Barnes and Noble this month) did very well and found her book supply pretty well depleted by day's end.
Add this to your Des Moines history bookshelf as soon as you can--though I suspect it will have more time in your hands than on the shelf!