Afraid to deploy before testing application...

I've spent the last year developing an application that I would now like to make available as shareware.

One thing is holding me back...

I've done enough in-house coding to know that no matter what I do, bugs will emerge once the app is exposed to "real" users and their various operating systems and processors. So, of course, before deploying the thing I would love to be able to subject the app to real-world testing -- not testing by me or a friend or a family member, but by someone who will use the app in a way that more closely resembles how someone who might buy it will use it.

Can any shareware authors -- or anyone else for the matter -- suggest how to best find people to test a program before its release?

What does the app do?

It's a file synchronization and backup program. Nothing earth-shattering. It includes an Internet component (it can copy and sync local files to an FTP server) -- given all the possible combinations of proxies and firewalls and ISPs, this is the primary part of the app that I would like to test a little more...

Thanks for your response.

Release as Beta. OR open source it. Maybe people won't USE it, but learn from it. Looks like a nice app BTW!