You want CSS.
Go to
http://www.w3schools.com/ and read the CSS tutorial. I hope you aren't using Dreamweaver or (shudders) Frontpage.
I don't know it very well, but a position: absolute should do it (look it up)
JBot
EDIT: Here's the page you are looking for:
http://www.w3schools.com/css/pr_class_position.asp
You will need to learn a little about CSS syntax, though.
Googling CSS position tutorial gave a few results:
http://www.brainjar.com/css/positioning/
http://www.tizag.com/cssT/position.php
http://www.yourhtmlsource.com/styles...csslayout.html
IMPORTANT: You have to know, what you want to do will not be very easy to make work in IE6 and back. Supposedly IE7 parses CSS correctly, but I can tell you from personal experience that a position: absolute does not work in IE6.