[CentOS] Live CD boot for KVM guest. How?

Hi,

My host and guest are CentOS 6. The guest is going to be a web server in 
production. I am trying to resize (extend) of the base partition of my 
guest.  But I can of course start the installation of CentOS 6 guest all 
over again with a larger image size. However, just for the sake of 
better understanding I an trying to solve things not to be end up in a 
dead end after some years.

1. I created a guest CentOS 6 with 12G total disk (on a iscsi drive). No 
Desktop, just for terminal use. No LVM, just a simple basic partitioning.
2. Later I wanted to increase the size of total image to 200G.
3. I managed to resize the image to 200G on my iscsi drive. So, there is 
188G unallocated/unformatted volume within the guest image.

Now, the hardest part. I have to resize the partition. I have been 
trying to find a way to do that. A search on Google showed that GParted 
is tool to do that. I had to install all Desktop and X as Gparted is a 
GUI tool. Installed vncserver. Then, I found out that GParted can not 
resize the live guest. So, I downloaded GParted Live CD.

Now, the questions:

1. If it was a physical machine I would boot from the CD. If I can boot 
it from host CDROM but then how should I operate on a specific guest? 
What is the easiest way to access GUI of the guest if I boot from Live CD.
2. I am wondering if a simple LVM route at the beginning would be 
preferred. Changing size of the iscsi volume on my NAS is easy. I 
thought there was no need for more complication, so went with basic 
/boot / and swap partitions. Is resizing partitions for LVM easier than 
basic partitioning (without LVM)?
3. Is there a specific tool in KVM suit which performs resizing 
partition within the image? Or as I prefer command line tools, is there 
a way to achieve resizing without any graphical tool like GParted? With 
GParted I had to install all the X and Gnome files, vncserver which 
otherwise I don't need.

I would appreciate any information/hint/experience.

All the best.