"Where all can you submit your articles to?"
You asked that from an SEO perspective, so that is where my opinion is going to come from.
People that blog and follow you on social media can be a good place to submit them to. (via Twitter, social networking, email, carrier pigeon...whatever works...grin) They are often better syndicators than the "syndicators". Why? Because they know you and value your expertise.
Here's a post by Joost de Valk on the power of doing that with Twitter:
http://yoast.com/twitter-clients/
Let folks in the industry know what you've written...truly connect and form relationships with them...and write killer stuff with substance. I know it sounds strange, but it works. Less posts , more friends, more substance.
Just my opinion.
Hope that helps.
Eric