Silly question, but if you submit your site to google... and they decide to sandbox you, do they send you an email or anything?
The sandbox isn't a real place, where you can see your site. Its simply the name for when your new site is placed lower in SERPs than it would if it were a newer site. Try to build up links and promote your site.
The sandbox is a name for NEW sites that get placed lower in the SERPS than they would if the domain and links to it were older. (previous poster turned it around).
So, is it better to have a new site, or an old one? I would have thought an older one would be better. Our site is actually pretty old, I think maybe even more than 5 years.