Hi, Kara! Thanks for the loaded question. I'm from Wisconsin too and the Milwaukee bargain hunting mentality is alive and well in this one. I guess that's a long way of saying that I'm pretty cheap. Here are some things I do to conserve costs:
Disney Rewards Visa Card. If you book your trip on your Disney Visa Card, you get special financing. This way, you could spread payment of the package over six months (at 0% APR) rather than all at once. Purchases also generate points for you that you could then have converted to a Disney rewards/ gift card to use on your trip. You'll get 10% off certain purchases too. One more perk: there's an exclusive character meet and greet at Epcot for card holders.
Value Resorts. Stay at one. Prices fluctuate based on the season. Check out Mousesavers.com for a grid that shows the cost of rooms at different times of year. Also check the Disney World page for
Special Offers.
Save on food. We bring breakfast items in our suitcase for most mornings. This saves us both money and time each day. If your family doesn't have a large appetite, stay away from the Dining Plan and share meals together (portions are usually pretty large at Disney World.)
Be thorough with flights. We've found that flights from Milwaukee to Orlando fluctuate a lot. We book our air before booking our trip. Why? Because we've seen it cost less to stay in Disney World an extra day (hotel and park tickets) when compared to the cost of flying out on the day we originally had in mind. Also look at Southwest. If you're flying out of MKE, their flights are usually cheapest and there's no fees for checking bags.
This should get you started. Feel free to follow up with us if you'd like help with specifics!