Flash 4 hours video will all about C :-)
Some videos by Jens
They need some cleanup , but here you can find them
There exist many tutorials around on the net.
Here is some of the best (my opinion)
C coding exercises - with solutions www.w3resource.com
When programming in C it can be nice to have an idea of syntax, library functions and so.
State Machines made simple in C:
Graphic programming for linux, windows and Mac