there are online versions if you fancy nonsense decisions based on general dribble soaked from the conscience being that is the intarweb.
http://www.gifworks.com/
gif builder on the mac has always been a staple of mine but ive moved to macromedia flash for accuracy as i have to export at limited filesizes for clients, so tweaking with flash is a breeze.
most magazines have specials with gif building programs.
The gimp will allow for multiple layers, im sure someone by now has scripted frames for gif building.
fireworks again with the macro prods indi will do it also
anyway enough ramblin, boring
try this
http://www.ausmall.com.au/freegraf/graphx04.htm
If no-one gives your an answer to a question you have asked, consider:- Is your question clear.- Did you ask nicely.- Are you showing any effort to solve the problem yourself 