I can tell you've been putting a lot into this, so you probably already saw the relevant wiki pages: http://wiki.warlight.net/index.php/Creating_map_visions
I also found a couple official tutorials on Google, but I'll spare you the LMGTFY link. ;) http://inkscape.org/doc/basic/tutorial-basic.html
Other than that, I guess you need to ask a specific question or show what you have. I, however, probably know less about Inkscape than you do; I was just browsing the forum.