In my virtual PC I have apache server; how can I access my vitual web server with my real machine(not virtual)

When you install your Virtual PC, it is also assigned a virtual network adapter and IP address for your virtual network.

Your phisical machine needs to be on the same network as the virtual computer.

Have options similar to these:

http://img23.imageshack.us/img23/8109/tryw.th.png

You do not want to use the same address as the host.