I have a Fiskars. This one.
http://www.joann.com/fiskars-rotary-...5.html#start=4
It works fine. But after quilting for 2 years I wish I'd bought one that has a blade which automatically retracts when you stop gripping the handle. I think perhaps the one I am thinking of is an Olfa as others have recommended. I am very conscientious about pushing the little button on mine to put the blade back into hiding but every once in a while I forget to do that. Unfortunately my cutter is in perfect shape still so I won't be replacing it any time soon. Plus I had a minor issue with it when it was new and Fiskars sent me a 2nd one, it's still in the package!
You should also get a cutting glove. I have a Klutz one. I got it when I started quilting after reading some horror stories on this board. If I cut without it on, I feel naked. Kind of like driving without a seatbelt. It's a good habit to have.
As to the cutting mat, when I started quilting I was advised to get the biggest one I could fit and afford. I got a Fiskars 24 x 36 and I have been very happy with it. It's been 2 years and a lot of cutting. It's reversible. The price was good at Joann's when they had 50% off all quilting supplies. I bought the mat, ruler and rotary cutter the same day.