Question: I would like to build a simple audio amplifier using transistors. I know there are IC designs specifically for the task. But i want to use transistors so i can learn how to use them for amplification.

How would I go about designing an audio amplifier from just discrete components.

Answer: 
If you want something simple to get started you could build this class A amplifier: 

![enter image description here](https://i.stack.imgur.com/xO68Y.gif) 

(from [this excellent site](http://www.electronics-tutorials.ws/amplifier/amp_5.html)). 
\$R\_E\$ stabilizes the DC setting, the bypass capacitor \$C\_E\$ is needed to allow an AC signal to change the output, otherwise \$R\_E\$ would try to keep the output constant.  

A class A amplifier is not very efficient. There will always flow a current through it to keep the output at Vcc/2.
I don't recall whether or not it uses transistors, but I'm positive Randy Sloan's excellent [Tab Guide to Understanding Electricity and Electronics](http://rads.stackoverflow.com/amzn/click/0071360573) contains an entry-level amp. Regardless, it's audio-centric so you will find many tasty things!