Most club players who use defensive signals will probably have 2 or 3 in their repetoir, which they will regularly use.
This book covers plenty more than that. However, it is very technical, and taking me an age to read and understand.
Unless you really want something technically very advanced (and remember your partner has to understand all your signals too!) I suggest reading the signals section of Mendelson's "Play your Cards Right" for starters. After you've mastered those with a regular partner, then you can contemplate reading this book (but as I said earlier, it's no use knowing lots of signals your partner doesn't understand, so make sure your partner reads it too, and you discuss in depth!)