Some gif animation programs (such as Jasc's Animation Shop) can save image sequences as AVI. You can get a free demo of it by downloading the latest version of Paint Shop Pro on http://www.jasc.com.

Furthermore, Animation Shop can't deal with sounds and editing very well, so an industry giant such as Adobe Premiere would do the trick. It's what I use for video creation, and I love it. It's mainly an editing program for footage, but nevertheless, it works well even if you'd get the idea to draw all individual images yourself.

Depending on the kind of movies you're after, a lot of 3D applications/renderers such as LightWave, 3D Studio MAX and MAYA can render animated sequences directly to AVI format. Takes some time to learn these programs though.

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