I am wondering about which programming languages people see fit to create a program idea that I had. I am looking to create a fairly simple program whose main functions are adding to, managing, and searching through a database of people, all through a polished GUI. It will be for use in the business world, so I think Windows would be the priority, but Mac and Linux support wouldn't be bad. Also, eventually I would like to add the ability for an instance of one program on a computer to interact with other instances on the same network, mainly through the sharing of a database.
Most of my experience is in Java, but I don't particularly like the appearance of Java GUIs, so I'm looking for an alternative. I noticed that a lot of people have suggested C++ or C# in similar posts, so what are some of the advantages/disadvantages of one or both if that is your suggestion.
Thanks for any help in advance.