Once you have completed this set of tutorials, you should be well on your way to being a seasoned C programmer! Recommended reading is The C Programming Language, 2nd Edition, Brian W. Kernighan and Dennis M. Ritchie. It is essential reading for all budding C developers, and covers many things not explained in this series of tutorials, or explains things to a greater detail. Programming your own projects is also a good way to learn. Contributing to open source projects is also an option once you feel your skills are good enough.