Below are several articles and links to useful sites with great information on the plethora of online learning opportunities available:
Articles at AdultStudent.com
Online Distance Learning Resources:
Sample colleges with online presence:
Miscellaneous Distance Learning / Life Learning
While many of the above links are focused on full-level coursework affiliated with accredited colleges and universities, the internet is full of many general (and technical) subject free tutorials. Below are a few links that have useful and fun tutorials on everything from computer usage to growing flowers.
Free Online Courses and Tutorials