I'm not great at sewing (would have to do it by hand since i don't have a machine ;_;)
You don't necessarily need a machine. I make my own by hand using the blanket stitch. It's sort of the same effect of using a zigzag stitch on a machine. Instead of putting the right sides together and then turning them right side out, I just layer it how I want it and then blanket stitch it all together with one strand of hand quilting thread. Like the kind of stitching that's around those little fleece blankets, only tighter. These take a little longer than the machine-stitched ones, but it's something to do while you watch TV or something.
They've outperformed the disposables and held up pretty well through the washer and dryer, so I can honestly tell you that being sewing-machine-less need not stand between you and free pads. OK, I did spend 99 cents at the thrift for a big sheet of waterproof crib pad for the bottom and a couple of bucks for some cute prints from the remnant bin for the top, but I already had the thread and ratty towels