You’re creating an amazing webcomic and still suffering in obscurity? Asking for links (nicely) from other webcomics is a tried and true tactic but you may want to look for fans who have yet to discover any webcomics at all. They may find your site because of its content, genre or other non-comic angles. But amongst the vast hinterlands of the Internet you’ve got to have a metaphorical flare gun to attract attention.
This page has some great advice on maximizing the visibility of your website pages to search engines.