Isolating Genomic DNA from a small colony of cultured human cells - (Sep/27/2011 )

I have some small colonies of breast cancer cells growing in culture that I want to isolate genomic DNA from. I plan to use the isolated genomic DNA as template for PCR reactions. I'm assuming that the genomic DNA will need to first be amplified before it can be used as template considering my colonies consist of ~100cells. Can anyone point me to protocols or kits that will allow me isolate and amplify genomic DNA from this small number of cultured human cells?
Thanks!

You shouldn't need to amplify the DNA, 100 cells =100 genomes, which should be enough DNA for a few PCRs.