Is there someplace to find all insurance companies to compare them?

Do you have a form or paper on the different types of senior supplement insurance in order to best compare apples to apples? We are moving to Montana and would like this report for the north-western segment of Montana. We are finding it difficult to locate such a report in Montana. We thought that there might be one here and one for the Columbia Falls, Montana area.Is there a number we can call to receive this report or paper for Montana.