The twentieth century has seen interesting developments in music - whether 'classical' or 'popular' music is in mind. But someone who dives straight into some of the more innovative music may find their ears are not quite ready for it yet! And so before listening to modern Latvian and other Baltic composers, you may want to start with a previous generation of composers from Latvia's more famous neighbors - Russia and Scandinavia. Here are some links to music you can freely listen to, and in some cases download:
http://www.vitaminic.com/cgi-php/src_eng.php3?text=Grieg&what=ALL&where=MP3&go.x=16&go.y=9
http://www.classicalarchives.com/main/s_hl.html
http://www.vitaminic.com/cgi-php/src_eng.php3?text=Sibelius&what=ALL&where=MP3&go.x=5&go.y=7
http://www.classicalarchives.com/main/r.html
http://www.classicalarchives.com/main/p_hl.html
http://www.epitonic.com/artists/dimitrishostakovich.html#tracks
http://www.epitonic.com/artists/mauriceravel.html#tracks