Where can i find a freeware program where I can control mouse clicks igned to different points on my screen?

Where can i find a simple freeware program where I can control mouse clicks igned to different points on my screen with my keyboard. I would also like to know if there is a way I could buy some sort of USB device like a keypad that I could customize and use to do these mouse clicks/macros. (ie I click a on and it clicks a specific point on the screen and i press another on and it clicks another igned position on the screen.)