I normally don't see any discounts for the machine itself, so these prior two postings are good deals on the machine. I got mine at CHA, so it was a good deal there through Wooten's Scrapbooking. They don't have an online store, unfortunately, but are located in Ontario and Tustin, so not too far for you.
As far as design cards, this thread is always posting deals from places such as ebay to your different web stores (stampingscrapping.com, scrap-mart.com, etc.,) you can google "Best prices for Slice Design Cards" and you should get a slew of sites.
I've got just about all the cards I'll need for a long time and got some great prices from ebay too for new cards there.
Good luck and have a blast with your new toy, it's so easy to use and you'll love it!!!