The Human Genome data can be downloaded in its entirety, chromosome by chromosome, in segments referred to as "contigs" (for "contiguous sequence"). This data, along with information about the location of genes and other biological features associated with the sequence, is available from NCBI's public FTP site.
For more information and sample searches illustrating how NCBI tools can be used for scientific discovery, see the Introduction to NCBI's Genome Resource or Take a Tour of the Draft Human Genome, both available http at the address above.