i'll answer your question in the best i can:
1. learn to draw on paper 1st. mostly realism( body, objects, environements, etc)
2. then try to learn some programs. flash can make some good frame by frame animation. stay away from tweens(computer made movements which look like shit-but can be useful in some case.)
3. if you want to make 2d, flash, toonboom or something similar is good. i recommend getting a tablet(wacom makes the best. a 6x8 is a good size)
4. if you want make it 3d, i recommend 3d studio max 8. there is an educational version. but the software is around 1000 for educational to 4000 or more depending on the plugins. if i'm allowed to say this: get the trial version and crack it if it's just to play around with it. for anything commercial, you need to buy a liscence.
5. now you cant just go and animate. you need to learn everything in the software. start with just modeling easy objects and then try to make anything. i go on Maxforums.org for my 3d info. the ppl there are super helpful just dont ask how to make a person(or whatever), ask more stuff like: i'm making a person, this is what i did up to now. i could realy use some help. crit my work plz! and then they'll tell you what to do. if you simply say: tell me how to make ****. they will bash you really fast! hehe
6.once you know how to make the objects, learn to texture, then eventualy light, then render. once you can do nice stills, learn the cameras, and timeline. but i still recommend doing 2d animation 1st to get your movements corect. it's pretty hard to get something good the 1st time.
7. finaly, use google for any more help. for example, plugins or tutorials are there for everyhing.
if you're gonna make characters in 3d, i recommend doing the Joan Of Arc Tutorial. it will explain it all in 1 good tutorial.
good luck!
edit: as an alternative, you could get blender. it's a 3d software that is FREE.
just google it plus: it's super small in size(mb).