If you have never used iGoogle before, it is available to anyone with a Google account. Simply login, and click the iGoogle link in the top right of the page.

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With your basic iGoogle page ready to be setup and used, the first thing to do is begin adding content. This can be done via the Add Stuff link in the upper right of the page. You can add stuff based on the selection displayed, Search for gadgets on the right, by category on the left or use the Add feed or gadget option to display an RSS feed. The main iGoogle page also allows you to arrange the gadgets for optimum use, simply by left-clicking the mouse and dragging the content to where you would like it to sit.
Once your gadgets are added, you’re ready to start using iGoogle - but not that you can also change your iGoogle theme if the basic Google look isn’t quite working for you.
Finally, iGoogle is also tabular – meaning you can add a range of gadgets to different tabs within the browser window. A great way of managing your iGoogle gadgets, you might organize them on a subjective basis, with one tab for work, another for social, a third for games, etc.