finding copy number - (Jun/02/2013 )

Hello,

I am looking at copy numbers for genes. I need to know if I find a gene with a copy number alteration (deletion or amplification), is there any website that will help me find the region of the alteration? Would this be the genomic coordinate? For example, if EGFR is listed to have 3 amplifications in a certain cancer, how do I find the exact coordinate of the amplification? What browser will display this for me?

Usually it's either simply duplicated at it's original site, or is it as a result of chromosomal multiplication.