Having just started training in Yoshinkan Aikido again after being away for 15 years, I've found that I returned to Aikido not to learn how to defend/combat but to develop physical strength, fitness & toughness, discipline and focus.

Through training I have learnt some basic self defense techniques that branch off from the basics of Aikido. However this may be due to my choice of Dojo (http://www.aikidoshudokan.com/).

Aikido as a system of forms and movements is about maintaining balance while controlling your partners/opponents balance. You'll find that most people will loose power once they are outside of their balance or off balance.

Give Aikido a go, also try some other martial arts! If you want to learn how to defend your self through being able to punch/kick etc I suggest you try Jeet Kune Do as this is a system that has been designed to get you up and running in a brief period of time!

But whatever you do, commit to it for a period of time... as you will only see development through a continuous effort.