Yes, there are online communities around pixel art.
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http://pixeljoint.com/-
http://pixelation.org/index.php?topic=4265.msg53067#msg53067Note that these places are best used for feedback rather than just plain text chat: you create a thread where you post things you've made and ask people to comment on them.
If you don't know where to start then collect a huge folder of reference images about the style you're trying to emulate. Pixel art, concepts etc.
Then using one of the many pixel art software that you can find online, try to recreate (100% copy) the pixel art that inspires you. This will force you to train your perception and learn a few tricks, like contrast, dithering etc. This will also help you get familiar with the software.
After you have done a few of these copies you will feel more confident to create something new, and this is where you can come in with your own designs and projects.