you can try http://www.mangatutorials.com/ but I find books are more helpful these days as they're better illustrated in my opinion... you also need to bear in mind whether you want to go with the traditional route (tonal paper etc) or computer graphics method (investing in a scanner and buying software)   O genki desu ka?

 I use many illostrators when it come to learning from books, in my opinion, David Okum is pretty good. If it's beasts and beings, J 'NeonDragon' Peffer is best. But if just for the characters, Lea Hernandez, David Okum... Thats all I can think of right now, ask at you local libary, they should be able to gat a hold of them for you.The night is undyingThe stars ablazeWhat will become of youWhen they are all but dust