From Pong to an RTS is quite a large step.
I would recommend something simpler like a simple FPS (simple AI and little flashy graphics - don't try to remake Halo) or if you are interested in strategy I found it quite easy to make a simple turn based strategy game. All it requires is a simple understanding of arrays. That was quite good as it was playable without any AI, which is by far the hardest part of any strategy game.
If you are still interested in RTS's and wish to jump in the shark pool immediately then I have a tutorial I downloaded ages ago and never really looked at:
http://www.2shared.com/document/HhUHtS7e/RTS_Tutorial.html