A general biography is here. For more on his failed romantic life, David Apatoff provides a summary here. For much more detail regarding Barton, you might was to read what The New Yorker published in 1989 here.
Also, Apatoff discussed Barton's art here.
Barton developed a simplified, modernist cartooning style during the 1910-20 decade and refined it during the 1920s. He usually relied on thin pen lines, areas of black plus washes to depict his usually exaggerated scenes. Some examples are below, but do take a look at the examples in the Apatoff links.