i am new to programming and want to develop a plugin that interacts with the itunes or winamp ar WMP and then does what it is programmed to do. I know php and mysql kind of stuff but i am totally new at programming for pc. my question is that how to start where to start and anything i should keep in mind . Stuff like best language to learn to do so. I know a little basic python .can it be used for making plugins?
You should start writing simple dll's (you can also write simple aplication to load and execute dll's procedures). Next step is to program better dll's (mor functionality etc.). There is a plenty of tutorials on this matters. And then you should read api documentation for application you're writing plugin to (for winamp check this site: http://dev.winamp.com/plugin-developers)