Michael Connelly is one of three favourite authors, the books are very good although some of the earlier ones can be a bit slow and perhaps focusing a little too much on Vietnam (less meaningful for a Brit born later than perhaps an older American reader). I've stopped reading books for the last year or two but I'd love to get the time to pick it up agian. One of the things I like about the TV series is it is (relative to some screen adaptations) reasonably true to the books, albeit they weave a few stories together from different books and obviously update things for the modern era (i.e. some of his earlier works are written in a time when information was much harder to come by, no widespread mobile phone or telecomms infrastructure, so some of the plot would be influenced by that, use of pagers/phone boxes, more painstaking research etc). If your profile age is accurate I don't think this should be a problem.
The Black Echo is perhaps not that accessible (I haven't read it in perhaps 10yrs but it felt quite slow with some abstract 'Nam stuff) so if you don't get on with it maybe try something like Trunk Music or Angel Falls.
. I really didn't take to Rodgers daughter. 