just so you know, animated gifs are nowhere NEARLY as powerful as flash is. gifs usually have crappy quality, and you have to do most of the animations by hand, or frame by frame.
i strongly suggest getting Adobe Flash CS3 (or whatever version) somehow if you want to get into web animation, as this is the leading technology. Other things like Microsoft Silverlight exist, but thats completely locked down by microsoft and i dont think they even have a software to make silverlight animations on the open market.