Recs for preschool workbooks?

[fsb2005]

I've been wanting to get Katie some little workbooks she can do for fun -- the earliest things like tracing letters, etc.  I'm not going to sit and make her do anything but I wanted to have something around in case she finds it interesting.  She's just not that excited by drawing and art, but I want her to get a little more practice holding a crayon and think she might actually enjoy things that are more like a challenge, and she's really into letters and numbers right now.

Anyway, I'll probably just go to the bookstore and browse, but anyone want to recommend some titles/series that they like?

Thanks!