You have really two practical choices here.
1)Use Gif animations which at 3-5 frames per second are serviceable - but have the advantage that tehy are self contained. All browsers support gif-animations without requiring any plugin;
Go here for free and shareware gif animators:
http://www.freedownloadscenter.com/Best ... -_gif.html
the one I use is Corel Animation Shop 3 its about $35.
OR
2)Use Flash animations from Adobe/Macromedia. The best and easiest intro to this is Swishmax:
http://www.crystalgraphics.com/flash/swishmax.main.asp
at $99. The official and high learning curve intro to Flash is available from
http://adobe.com and cost about $300-500. Advanatge - everything is possible with Flash!
Disadvanatge: Big learning curve because most animation stuff is done programmatically with ActionScript - a JavaScript clone. There are Flash software packages that hide programming like Swishmax and Toon Boom Studio but they have prices all over the place ($99 to 500) and are always a step or two behind the latest Flash features.
So choose your poison
Just to add insult to injury Microsoft has added its own non-standard animation tool for Vista called Sparkle (part of the Expression suite for upcoming Vista OS) and the standard for animations, SVG, is slowly but surely starting to pick up adherents especially in the field of mapping, simulations, and high end product design.
Finally go here for rippling water :
http://www.2006ccwc.com/
using Flash and rip it off!