hi, Adam's antiquities looks like a great book – I read the first chapter last night online and I've decided to read the whole thing: many thanks for the reference.
it seems (from the part I've read so far) to limit its evidence to classical literary sources and doesn't cover archaeological evidence etc., and so if you combine reading a chapter of this book (e.g. the chapter on COMITIA, pg 54 + ff.) with a recent study of the same area (e.g. Mouritsen's Plebs and Politics in Late Republican Rome, 2001 which is another good book worth reading: here's a review: http://bmcr.brynmawr.edu/2001/2001-12-12.html
) you'll have a good basic understanding of the topic. i think this would be a better approach than just jumping straight into the recent studies themselves – Adam's book covers well the latin vocab for each topic, which will help you understand better the recent studies.