What are you trying to do that you can't do with the languages you've already dabbled in?
If it's something specific, ask about that. If you're just learning to program in order to learn to program, you'll probably burn out before you get anywhere useful.
Have a project in mind then tackle it with whatever tool you're already most comfortable with. This will keep you motivated during the learning curve.
Once you've done it one one language, try tackling it again in a new language so that you can start with a base of familiarity which will highlight the differences between languages much better for you as you progress.
I'm not an expert coder but I've created projects in cp/m, fortran, basic (oldschool!), pascal, visual basic, c, c++, java, python, perl, javascript, c#(.net), php and Ruby so far, with more to come. The only way I managed to keep from gouging out my own eyeballs with frustration was tackling specific problems with each new language. Now that I'm getting more heavily involved in web programming the background with each of these tools is helping me to make decisions in a way I couldn't if I hadn't tinkered with all of them.
So my advice is: fix a problem that you currently have in any language you want. Rinse repeat.
