Yes, I've drawn Tomoyo (called Madison in the English version), but I think Toya is my favourite character. Growing up it used to be Yuki (Yukito/Julian), but as I grew older in my periodic returns to the series I really began to respect and love how great of an older brother Toya is.
I love how much he loves Sakura, especially in his encounter with The Mirror. That story is probably the one within the series that sticks out most to me, just because pain can't keep Toya from his sister.
I also like the underlying romantic implications Clamp is great at slipping in to their stories, the relationship between Yuki and Toya being no exception.
Anyway, yeah so here's Tomoyo, a great best friend to Sakura, super cute, super creative, loyal, ect. A bunch of the attributes that the best of friends should have.
Done in Photoshop CS 5.2
Based on the traditional drawing shown below.