Doug, Don, ditch the books for fieldwork and ID purposes!
I follow along when all the North American birds are posted on this thread and often look them up - either to ID them when unknown or just read further details of them.
And to do this I bought IBird Pro which I use on my Smartphone. I went for an app as years ago I ditched my books and prefer to now use apps for ID.
Much easier and quicker to use firstly, and secondly they are always with you.
The IBird Pro is the best North American one I could find and conforms with all the other bird ID apps., having drawings, photos, unique ID marks, call and vocalisation records, a birding search engine, and also an option to buy an additional AI photo-based recognition feature.
Have a look....
https://play.google.com/store/apps/d...bird.pro&hl=en I really do recommend this for your birding. The drawings can also be printed out and are of frameable quality.
And for anyone needing a South African App - look no further than here. This is by far the best (and also globally one of the best terms of design and feature use)...
https://play.google.com/store/apps/d...abirding&hl=en