I am using the VMWare server 1.0.8 with Windows XP as host and Ubuntu 8.1 as guest
Select your Network interface for type for the Guest OS

Configure the selected card in VMWare setting

Choose the Network IP 192.168.0.0 and click ok
Configure DHCP server for NAT I've set IP range 192.168.1.124 - 192.168.1.254


Open up a terminal ...

..and type
sudo gedit /etc/network/interfaces
This wil give you a window like the one below.
add the following lines
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp

Now we need to setup inetrnet connection sharing in windows
Select the Local Area Connection properties >> Advanced tab >> Check internet connection sharing and select the Vmnet8


Now return t your Ubuntu and run
sudo /etc/init.d/networking restart

Congrats!! Your're done. Now you can browse the web from your guest Virtual Machine