Here's a list of the best-selling comics and graphic novels for February 2003:
http://www.comicbookresources.com/news/newsitem.cgi?
id=2066
The books with female lead characters in the top 300 comics are (in descending order, and leaving out team books unless all the leads are female):
Batgirl Elektra Alias Wonder Woman Witchblade Tomb Raider Supergirl Birds of Prey Lady Death Fables Ghost in the Shell Catwoman Fathom Soujourn Spider-Girl Chimera Harley Quinn Danger Girl Lady Constantine Buffy the Vampire Slayer Mystic Strangers in Paradise Meridian Athena Inc. Sandscape Eden's Trail Vampi Zero Girl Powerpuff Girls Grrl Scouts Queen and Country Banzai Girl Shi Battle Angel Alita Cardcaptor Sakura Courtney Crumrin Dogwitch Betty and Veronica Sabrina Jungle Fantasy Promethea My Monkey's Name is Jennifer
Is that any help? I'd say there's milage in a fair few of these.