As far as I'm aware of
Mono is the only app available that'll port the .NET Framework to Linux, as well as OS 10.
You can still use WINE though to run Windows apps on Linux.
I do remember using
Gambas back in 09. It's probably the closest thing to Visual Basic you'll come to for Linux. Unless you want to get Mono Tools to make .NET apps, but Mono is great just for running it on Linux.
Although back in 09 I heard of
vb4linux however. Doesn't look like any progress has happened sense then, cause there hasn't been a build released yet, but still it's something to look into.
I would advise you to learn C, and/or Python if you're gonna develop apps on Linux, cause you can use CMake which is a cross platform compiler, and make your application be able to run on Windows, Linux, Unix, and OS 10.
You could also download, and install the
Eclipse IDE and develop Java applications. Which is good to learn, cause Java is cross platform, and a lot of Android apps are developed in it.