I like to move certain songs into specially named folders to organize my music. If you do this you can use a freely downloadable program, such as TagScanner (http://xdlab.ru), open up the contents of an entire folder, select all (ctrl+a) files in the folder and type in or select something for Genre. Takes a few seconds to change the tag of all. Once you transfer the songs to your phone the software should be able to make a playlist of all songs of the same genre. If it uses “categories” or some other name, you can find another way to bridge the gap using TagScanner (or other software – you should be able to find lots at http://download.com).
More of my computer tips.