You can hire a car in Iceland, drive around and stay in B+Bs (or hotels) like any where else. Eat out in restaurants, too, but it will be very very expensive. Most things are quite dear in Iceland. That won't take away from the spectacular scenary, of course.
But an awful lot of visitors opt for camping. And cycle touring and camping is one of the best ways of all to see the country. You have to be prepared for the elements, but there's nothing to beat experiencing the landscape through all of your senses.
Otherwise, a few tips. Change your money in Iceland (when arriving and before leaving), they'll give you better rates there than outside the country. Also, bring as much gourmet food as custom regulations allow; only the most basic staples are a reasonable price. And plan for variable weather.