Here is an example of one such genre. Until relatively recently, Italian Baroque opera (when it has formed any part of a modern opera company's repertory) has been primarily associated with figures from the late Baroque, especially Handel. But for those who want to discover a ravishingly beautiful repertoire of works that are infrequently performed today, recording technology has proved a godsend. It is possible to find (although they are still not very common) recordings of operas by Benedetto Ferrari and Francesco Cavalli, two of the most important composers of mid-seventeenth-century opera, as well as works by the slightly later composers Alessandro Scarlatti and Alessandro Stradella.

Although not many of these composers' operas are available on CD, some of their smaller-scale works, particuarly the secular cantatas, are being recorded in increasing numbers. There are also numerous recordings to choose from of Monteverdi's three surviving operas, Orfeo (1607), Il ritorno d'Ulisse (1639), and L'incoronazione di Poppea (1641). Of these, Poppea comes closest to conveying the idea of these early Venetian public operas.

Something to be aware of when looking for recordings of music of the period is that the voice parts are sung by the appropriate voice type. Since we no longer have castrati, this means that male countertenors, or women, will often sing the original high-voiced male roles. Another consideration is whether the recording uses historical instruments or not. Some people prefer to have the most "historically accurate" performance possible; others consider the general quality, whichever instruments are used, to be of primary importance. One can make a case for either point of view. Ideally, one listens to a couple of different performances for a sense of the possible range of interpretations.

The reason there is such a range is that surviving sources for many of the musical works are infuriatingly incomplete and sometimes contradictory. It's often a musicological sleuthing job to piece together the original version of a work. The following list of recommended recordings is by no means comprehensive, and represents only my personal preferences.

Recommended reading
The early seventeenth century is still relatively unexplored by scholars, and many of the books and articles that deal with the period are highly technical and require a relatively sophisticated musical background. However, the sources below can be approached by anyone who can read music, especially since one can always simply skip over the more technically oriented sections if necessary and still gain a great deal.

Claude V. Palisca, Baroque Music (Prentice Hall, 3rd Edition, 1991).
This is one of the shortest surveys of the entire period, but it is remarkably thorough. Palisca's knowledge of the field is encyclopedic, and he tries to pack a lot of information into this volume. Occasionally this approach can result in ellipses that can be a little confusing for those who lack a thorough musical background, but the work is still a good starting point for someone interested in the Baroque.

Claude Palisca, The Florentine Camerata (New Haven: Yale University Press, 1989).
This beautiful book collects and translates many of the writings of the influential Camerata and provides a sense of their philosophical and aesthetic agenda.

From the "Music & Society" series: The Early Baroque Era, ed. Curtis Price (Englewood Cliffs: Prentice Hall, 1993).
This work is a great collection of essays that concentrates primarily on the historical background of the Baroque in many different European centers. It is therefore a good volume for people without an extensive musical background.

Ellen Rosand, Opera in 17th-Century Venice: The Creation of a Genre (Berkeley: University of California Press, 1991).
Rosand's book is the definitive work on early Venetian public opera. It contains a wealth of historical background, which makes it approachable by nonspecialists, but it also includes in-depth musical examples.

Lorenzo Bianconi, Music in the Seventeenth Century (Cambridge: Cambridge University Press, 1982).
This work is one of my favorite sources about the period. Bianconi's Italian bias is apparent, but the book is lucidly written and quite detailed. To tackle this book, it is helpful to be comfortable with technical music terminology.

Manfred Bukofzer, Music in the Baroque Era (New York: W.W. Norton, 1947).
This work is still a mainstay of the period, written by one of the foremost experts. It is also more approachable, with a fairly extensive music background, and it extends throughout the Baroque period, through Bach and Handel. Bukofzer's Germanic bias is apparent, however, and he doesn't explore opera quite as thoroughly as Bianconi.

Women Making Music, eds. Jane Bowers and Judith Tick (Urbana and Chicago: University of Illinois Press, 1987).
This book is a great collection of essays on women composers and musicians throughout history, with some good articles on women from the early Baroque era, including one by Ellen Rosand about Barbara Strozzi.

Leeman Perkins, Music in the Age of the Renaissance (New York: W.W. Norton, 1999). This monumental work is a treasure trove of information about music of the Renaissance. Although there is much to appeal to the serious music scholar, there are also many sections that are quite approachable by those with a more limited knowledge of music.