I have a Wired DSL Connection in my laptop, and I want to share this creating a hotspot.
Ubuntu 12.04
Dell Inspiron 1545
What you are looking for is referred to as "ad-hoc" networking. Simply clicking the networking icon in the panel, and then clicking again on Create New Wireless Network
should lead you to a point where further guidance is no longer necessary.
Should you want more information, perhaps about editing or deleting such networks, you can find some of my writings on How to Ubuntu.