Popular Music History?

Heya, I need to learn about popular music history, preferably as much as I can over the next 5 weeks college/ school holidays as I'm really weak on the subject.





I need to learn from the start i.e. African American work songs to present, It seem really difficult to categorise, with classical music you can divide it in to periods (ancient, medieval, renaissance, baroque, classical, romantic) and 20th century classical (nationalism, impressionism, expressionism, neoclassical and minimalism) and i have produced mind maps for them and the main composers but with popular music its really confusing with so many overlaps and almost random styles developing like reggae, which seems to come from nowhere from jazz and blues; as you can see I lack a lot of knowledge in popular music, anyone suggest a book or website that is concise (those not endless waffle) on popular music and an overview on how it developed, i really have to learn about the main styles ragtime, blues, jazz, rhythm and blues, soul, reggae, ska, punk, rock, metal, disco, electronic dance etc, I would like a reasonably in depth book on all them if i could, i got a great book on western classical music history which divides everything up in a logical order but I am yet to find any consistent books on popular music.





Note: Wikipedia isn't helping!!





Thanks for reading, all help will be very much appreciated :D|||One idea is to go to allmusic and for each genre and sub-genre they have a description of what it is and roots plus best artists, albums and songs. Here is the one for Ska:





http://www.allmusic.com/explore/style/sk鈥?/a>|||heres a video


http://youtu.be/oHg5SJYRHA0