Creating animations in WPF is easier than it sounds. No explicit use of timers is required, in fact you can create many useful animations using pure markup (XAML). Perhaps the best use of animations is to spice up UI. Most properties of objects can be animated (e.g. width, height, color, position, etc). Want your button to fade to a new color when a user mouses over it? Want your text to quickly slide into view rather than just abruptly appear? Of course once you see how easy WPF animations are you might be in danger of overdoing it and creating some truly garish and annoying apps but that's why you like programming - because you have courage.
Ok, here's a link to the SDK's introduction to Animations. http://msdn2.microsoft.com/en-us/library/ms752312.aspx
This overview introduces the core principals of animations with examples. Currently it has a rating of 5 out of 5 stars because it's quality. Read it carefully and you'll have a great base for all your animation adventures. Once you have finished this, if you feel you need more, check out some of the other overviews for animations at http://msdn2.microsoft.com/en-us/library/ms749238.aspx.
In addition, there are a number of smaller "How to" articles that demonstrate specific animation scenarios. There are a ton of these so you may find yourself browsing around for a bit. Here are the links to the How-to articles:
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