We joke that while we know where we will be in, say March, 2014 (India), we don't know where we will be tomorrow night. But it is the truth!
Planning is a day-to-day thing. Often we will decide to stay over for a couple of days if we especially like a place or if the weather is particulary nice, or rotten. We use booking.com to find lodging, usually the day before. The rates are good and we can program the address into the GPS for hassle-free (usually) guidance. And don't believe the "only 2 rooms left" hype on the website. We have booked the "last one" room only to find ourselves staying in an empty hotel!
Palmeral of Elche
A guide book, currently Rick Steve's Spain but usually something from Lonely Planet, provides the general recipe. Googling World Heritage sites, birdiing hotspots and national parks adds some spice and local advice is always appreciated. Flexiblilty is the name of the game!