I like those giant mousepads, but pretty much any of the popular mousepad companies are gonna be the same. I have an XTrac XXl it covers my whole keyboard mouse area and it works really well. Also yeah you can just buy them off amazon, any of the popular brands are gonna be just about the same thing.
There are different types however, and different surface materials: You can get the traditional semi-rigid mousemat with the foam base and plastic-ish surface, a cloth mousemat which is basically the traditional mousemat but with a soft fabric surface so you can roll it up and wash it and such, a rigid mousemat which is basically a piece of plastic with an optimised surface that you put down on your desk and go (I have this type). Finally you have the best of the best; the solid glass mouse surface, basically a pane of glass that has been formed or treated or whatever in such a way that it returns lasers back to the mouse properly.
The differences (as far as my own experiences go) are that the cloth mouse mat can be rolled up, moved around easily and put in the washing machine (carefully), they generally feel quite comfortable to have the ball of your palm on or your wrist if you use that sort of grip though the friction on your mouse can be quite high and may require more force to move than on other types of mousemat. The rigid mousemat (that I'm using) has an optimised surface, that means that it has thousands/millions of pock-marks in it and results in considerably less friction than cloth and traditional mouse mats, the only real issue is that it's a little difficult to clean and the surface can ruin the feet on your mouse depending on what material they're made from and especially if you're heavy-handed and apply downward force to your mouse while using it. Finally the glass mouse surface is just all around better than the other methods; it's easy to clean, every optical/laser mouse works well on them and the surface is so smooth that mice just fly on them. The obvious downsides are the price, the fragile nature of glass and the weight (difficult to transport), and the fact that they can be very very cold in the morning and they're not incredibly comfortable to have your wrist/ball of palm rest on.
You can probably find better guides to the different types on Google but these are what I know from my own experience
