Thanks guys. Just wanted to add that I used a program called Pixelmator to do the graphics work.
The "subtitle" of Pixelmator is "Image editing for the rest of us", indicating that if you're not a pro used to work with tools like Photo Shop, you are at the right place with Pixelmator.
And how true it is. It's by far the easiest, most comfortable and powerful graphics editing tool I've used so far. It's also very well making use of Snow Leopard's power.....
For the Mac users, you can't live without it:
http://www.pixelmator.com/For non-Mac users: buy a Mac and get Pixelmator and see the difference
