You will need glib2, dh-autoreconf already installed. To install, execute:

sudo apt-get install libglib2.0-dev dh-autoreconf

Get the latest version of qemu from the repositories:

• Get qemu source code

  I am using version 1.7 for this.

Extract the tar ball:

tar xvjf qemu-1.7.0.tar.bz2

Go to the directory where it has been extracted using cd <path>.

Check for dependencies and create the makefile using:

./configure

Compile the source using:

make

This make take some time; rough 30 minutes and then, to move the files to the appropriate locations using

sudo make install

Now, qemu-system-x86_64 --version should give you

QEMU emulator version 1.7.0, Copyright (c) 2003-2008 Fabrice Bellard

If you encounter any error at any of the above stages, you need to resolve that first before you proceed.

I have written a blog post on this, you can have have a look at it here:

My blog post on compiling qemu from source.

Feel free to ask for doubts as comments.