In my opinion, you never can know "enough" programming languages. The first (programming) language you learn is the hardest, the second is much easier, and after the third, it almost becomes easy.

You should look at what strengths Visual Basic .net has to offer - for example the very easy and convenient designing of user interfaces and its very transparent integration and interoperation with other Win32 components and applications.

For example, demerphq is using Visual Basic frontend programs to launch and configure Perl programs which do the hard work.

Of course, you can always think that you wasted your money, because in the end, everything that Visual Basic can do can also be done in Perl, much in the same way that you can use a chain-saw to hammer in nails as well - learn your tools and their strengths, weaknesses and common uses is the advice I can give to you.