You don't need much for that job. The type that are a straight handle with a wheel are all you need, like this one:
You can get them at hardware or craft stores too.
Go to Lowes/Home Depot/your preferred hardware store and buy some window glass (float glass), or find some old float glass from a garage sale picture frame/whatever. It's really cheap. Then watch some Youtube videos. Practice on a different piece before cutting anything you care about. It's not hard, but you do need a feel for it since it's easy to make mistakes you can't fix.
It's important to keep the cutter perpendicular to the glass and to get a nice smooth quick motion to get a good score. You don't need to grind the cutter in, a relatively shallow score works fine (you do need to apply some pressure, just not much). If you're just cutting a straight line, you can use a ruler/yardstick/whatever to kelp keep the cut straight.
The edges are the hard part, you can use wet/dry and work them, but it's slow going. There are diamond hand pads that work much faster, but they are probably out of your budget.
Last edited by fisheye; 08-27-2013 at 03:19 PM.
Reason: fixed typo