You can either skin the original H300 firmware with a program called H3mod, or I would suggest at looking into putting Rockbox on you player which offers a much more customisable WPS (while playing screen) and has features like album art.
You can download h3mod here...
http://www.cerebus.de/iriver/
...and ready made skins to import into H3mod here...
Completed Themes/Skins
You can find out about Rockbox on the Rockbox site...
http://www.rockbox.org/