No, netbooks in general are made for internet/email use and maybe simple computing. Therefore, a quad core processor in a netbook would be like a race care engine in a lawn mower. Like stated above, you could build a netbook with a quad core processor, but again I feel a processor of the strength would not be fully utilized with other common netbook specs.
There is in fact an Acer netbook with a quad core processor. The Acer Aspire One 522 Netbook has recently been introduced. It uses the same technology available to quad core processor machines. It is available at many computer shops including Amazon for about 320 bucks.