Hi there!
There are tons of ideas and documents out there how to design a game. Personally, im a "learning by doing" person.
The best tutors are most likley the games you like to play. Maybe its a idea, a game aspect you are interested but other games did not touch this part etc.
Because you say you are a programmer i think you already know how to design code etc. so you are more interested in the creativity aspect.
So first, you need an idea. Maybe its the idea "i want to make a cyber punk adventure" or "i want to combine adventure with RPG elements", the your first idea is what you need.
A great source from a more theoretical point of view (please note, he talks about commercial game design, not the hobby aspect of indie game design so dont be misscouraged if he said you have to be in the bizz to get your game done):
http://www.sloperama.com/advice.htmlAn other great source is Brass Latern. Its focus is on text adventures like ZORK but the documents also work for graphic adventures:
http://www.brasslantern.org/writers/http://www.brasslantern.org/writers/design/Then i would say you should take a look at gamasutra. Its the main news place for international game development. While its focus now is more on industry news, its bigges plus are their featured articles. Interviews with designers, background technology articles etc. For example the last feature i read was Peter Molyneux article about user interaction. Simply a great source for ideas and optimizing game development.
http://www.gamasutra.comfor graphics, the best solution would be to find ressources or your own graphic artist. Also, dont set your exspections to high. If you do this in your free time, you will most likely not challange game graphic like Still Life without drasticly reducing your content.