Have you tried emailing Sony support to see if they will have mercy on you and give you a replacement CD with the burning software? Maybe if you registered your drive, they will accommodate you.
What burning software do you own that isn't working for you? Anything? If not, then you don't have a lot of choices. You either have to buy a package or use a free one. However, free burning packages tend to have limited capabilities and are difficult to use, so I wouldn't recommend that option for a less experienced user like you.