Como ver packages instalados

[fearlex]

Osea respondeme esto, los plugins donde se instalan, en /usr/share ???
ok para ke me entiendas, yo instale el plugins de flash usando la siguiente sentencia :

yum --enablerepo=flash install flash-plugin

y se instalo perfectamente, e instale el plugin de MP3 siguiendo las siguientes indicaciones de la Fedorafaq.org :
Q: How do I play MP3s in Fedora?
A: Before I talk about this, you should know: In the United States and some other countries, you may have to pay patent royalties to use MP3 players or encoders. However, for home users, there is no legal problem with MP3 players. (Thanks to Doug McClean for clearing that up for me!)

With that said, the plugins for these things are usually in the rpm.livna.org repository. You install a different package depending on which Fedora MP3 player you want to use. If you're not sure which one to pick, Rhythmbox is the standard. It's in the "Applications" menu, under "Sound & Video" -- it's called "Music Player."

Here's how to install the correct MP3 plugin:
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1. Make sure that you're using my yum configuration.
2. Open a terminal.
3. Become root:

su -
4. Now, install the correct plugin depending on which MP3 player you want to use:
* For Rythmbox or Totem:

yum install gstreamer-plugins-mp3
* For XMMS:

yum install xmms-mp3
* For KDE MP3 players, like Noatun or Juk:

yum install kdemultimedia-extras

Now you should be able to play MP3s your favorite Fedora MP3 player!
entonces aun asi no se reproducen los mp3, por esta razon kiero como volver a instalarlo, 1- para poder aprenderme el proceso y 2 para poder hacer pruebas antes y despues, y conocer el proceso, me explico, gracias amigo.