1.The Perfect 3 Column Liquid Layout (Percentage widths)

http://matthewjamestaylor.com/blog/perfect-3-column.htm

2.

http://stackoverflow.com/questions/20566660/3-column-layout-html-css

<div class="container">
   <div class="column-center">Column center</div>
   <div class="column-left">Column left</div>
   <div class="column-right">Column right</div>
</div>

----------------------------------------------------
|              |                   |               |
| Column left  |   Column center   | Column right  |
|              |                   |               |
----------------------------------------------------

.column-left{ float: left; width: 33%; }
.column-right{ float: right; width: 33%; }
.column-center{ display: inline-block; width: 33%; }

DEMO

3.

http://www.dynamicdrive.com/style/layouts/category/C10/