Chris,
Sounds like me, except mine was unpacked a year ago!
The book is in Spanish and it's called "52 excursiones alrededor de Madrid" (en bicicleta). I bought it 9 years ago so don't know if it's still around. It's published by El Pais Aguilar. It has a nifty velcro "carpeta" with loose pages so you can just take one with you in your map pouch.