Wow, lots of great advice. I would just like to add a couple of things that I use to save for those "big" expenses (like WDW).
Let me first say that I quit work 2 years ago to raise our children (and homeschool). We LOST 2/3 of our income because of that. I can say that I've picked up a few tricks out of necessity and I can't believe how much money we used to WASTE!!!
First, I've been to every library around our town. Did you know you can borrow movies for FREE??? We very rarely rent a movie anymore and when we do we take advantage of specials and coupons (at Blockbuster's you can get a 2nd "old" movie when you rent a current movie early in the week). The best library around has a great stock of DVD's as well as videos. Wonderful way to rent movies you missed and kids movies. Watch out for returning movies late, but you usually get at least 1 week (one library gives us 3 weeks!!!) On our "libary day", I make sure to combine the trip with other errands to save on gas money.
Second, this works great for me, before you buy ANYTHING ask yourself "do I really need this or would I rather spend this $ on Disney?" That really cuts down on spur of the moment spending. I use this while I grocery shop, too.
Third, the "spend no money this week" idea sounds great. I do a variation of this with groceries. Have you REALLY looked at what's in the back of your cupboards? If they're like mine, there's food in there, just waiting to be fixed. Have a "clean out the cupboards" week and use the stuff in there!!!
Fourth, don't be afraid to try the cheaper variations on products. I can't believe what I used to spend on "Jone's of NY" skirts and blazers and such. NEVER again!!! I buy generic pop, skip "treats" until they're on sale, buy in bulk when cheaper, and make my clothes last and last. Do I really need another pair of shoes? I'd rather save for Disney.
Of course, I do the ebay thing at times and shop garage sales and second hand places. I ONLY buy items that I LOVE and NEED and I never want my kids to look like they have hand me downs on, but you won't believe what you find at garage sales that have never even been worn!!!!
Lastly, I find that I won't spend money if I don't shop (duh)!!!! I have to stay away from the mall and certain areas of Walmart or I buy without thinking.
Hope this helps in some way. Good luck with your goal. Just think how great it will be when you make it (maybe even early)!!!!