We had taken a small weekend trip to Madikeri to escape Bangalore in 2005 summer. Frankly it was not the best time to visit, but there are always some takeaways. I would recommend a trip between Oct-Mar, when there is water on the riverbed and the waterfalls. Some cool over the place, so you can hike it well.

For stay it should be a Kodagu family you should stay with. The food they can cook is out of the world,  real effort spent in making each ingredient stand out. And if I can generalize, the overall experience is  quite warm and homely.
Many people there have cottages in Madikeri, high up and coffee estates down in the lower hills. So while you can cool off the day’s start at Madikeri, drive down to the estate to listen to only the sound of dry leaves crushing under your foot, :). If you are a little adventurous there is a bit of rock to climb around too.

The inside roads are pretty bad, bad and as I understood from the Coorgi people, since the day Coorg was amalgamated with Karnataka, there has been step treatment by the state government. Pity, for its a huge, pristine mini-state by itself that can really be great for tourists. Go there to get a perspective on how small city life really is.

I had bought the Travel guide by Outlook to help me about the place and found it useful, but help if they can add some more maps here. Some pictures to help.