duno if this is will help, but when I started trying to draw anime characters, I kept trying to mimic one character and all i found that did was make it look like a 'diet-coke' version of that character, the eyes not quite right and such.
The way I got around this was by looking at loads of different anime characters, and you soon see that once you familiarise yourself with different character designs in the anime style you see their differences and similarities and you begin to 'get to grips' with the whole proportions, eyes, colours and postures so that you can express yourself in the style.
E.g.
Megaman Zero (large eyes, small build, slim, futuristic)
Prominent artists in this style: (C.L.A.M.P, The Kishimoto bros, Akira Toriyama).
Kusanagi Kyo (thin build, realism, drama)
Prominent artists in this style: (Kouta Hirano, Tetsuya Nomura, Shinkiro)
(Wikipedia should give you a list of all the stuff these guys have done).
P.S. I personally, don't recommend 'how to draw manga' books.
---
@ Roxas - Nice Rinoa.
Kez: Legacy of the Flame