Bill Mounce has an interesting post on ekklesia, the word commonly used for church. But the post is not really a word study or a study of specific texts. Rather it is a theological and personal exploration of the topic. This is of course is fine as far as it goes, but it would, in my opinion, have been better to have the latter supported by a more rigorous examination of the former. In any case, you can read Mounce's post here.