ARP, ARP, baby...

ARP- address resolution protocol

according to wikipedia : http://en.wikipedia.org/wiki/Address_Resolution_Protocol

Address Resolution Protocol (ARP) is a telecommunications protocol used for resolution of network layer addresses into link layer addresses, a critical function in multiple-access networks. ARP was defined by RFC 826

and there you have it...

a host wants to send an unknown host a mess,
DNS supplies the host  unkown's IP address
layer 2 has no clue
it ARP's for the cue
so IP is assigned a hardware address

sorry...