Hi! And Welcome Back!
I operated with DC since the early '60s, and made the switch to DCC at the same time I began building a new layout in early 2009. It was not an easy decision, but I am very glad I did it.
The Kalmbach books mentioned were (are still) a big help, as was reading this forum and asking lots of questions. Thankfully, the good folks here were pretty patient, and helpful.
The thing that held me up in making the switch was that DCC looked extremely complicated and it appeared a whole lot of electronics expertise was needed. The truth is (to me of course), it is relatively easy to get DCC equipped trains up and running and the basic wiring is pretty straight forward. If you choose to get more involved (i.e. signaling, DCC operation of turnouts & accessories, automatic routing, etc., etc.), it does get more complicated and more expertise is needed.
Installing decoders in locos ranges from pretty easy to fairly difficult, depending on the loco and whether or not it is ready for DCC, and other factors. In my case, I bought a number of locos with DCC installed (and sound!!!), and my remaining fleet was pared down to those that were not very difficult to install decoders.
Depending on the size of your layout (mine is HO, 11x15, two level), and your operational needs, DCC can be pretty costly. I’ve got about $2k in the system and decoders, but you can start out in steps and not spend a whole lot of money at once. Oh, one other thing… which system to buy is a frequent question on this forum. I liken it to the question, "which is better, Ford, Chevy, Dodge, Pontiac?, of my car nut youth. The big players are Digitrax and NCE, with MRC, Bachmann, and Lenz not far behind.
GOOD LUCK !!!
Mobilman44