Welcome to the community, Stardust!
Windrider will be posting the guidelines for the 2011 calendar in the next few weeks, I think.
But in the meantime:
The competition is open to all?
Yes!
I have to ask permission?
Nope, you don't need anyone's permission.
Where I insert drawings?
Windrider's post will answer this.
It 's already been decided on the theme and format for drawings?
I believe so. The theme that won was "Hidden Moments", and it sounds like we were going to stay with the format of 3300 x 2550 pixels (11" x 8.5" at 300dpi). But, again, her post will include this information.