I am SO excited!!! My hubby gave me a cricut expression for Christmas (My very first cricut!!!!). I got the chance to play with it yesterday. I am really loving it! I do have a few questions for you seasoned cricuteers... I love the cartridge that comes with my machine, but I would like to get more to play with. Where can I go for the best price on cartridges? How long (with average use) will the cutting mats / blades last? Is there a way to extend the life of the cutting mat? Any tips or tricks that I need to know?