I am planning on going in June. Many places that are reasonably priced are already booked or prices have doubled since I started booking in October. We are renting a car and doing the ring road. We haven't booked any tours and are not really planning to. There are many travel books on Iceland and lots of info online. Airfares are very reasonable now but mostly everything else is quite expensive. You need to decide if you want to camp, hostels, guest houses, hotels or self catering. Many of the hotels and guest houses come with breakfast. You didn't say how many days you're planning?