We went Easter 08 for 28 days. A family of 4 for just over £3500.
Whole lot booked online. We searched for flights and accomodation with many online brokers, like Opodo, Kayak, travelocity, Travel supermarket etc etc . Booked connectin flights with Continental for just under £300 per head. We flew LHR to Houston Texas then Houston to Orlando. All in one day. Return was Orlando to Newark and then to London again.
We booked a condo (Blue Heron Beach Resort) as opposed to a villas as I didnt want to get stung with 4 weeks of pool heating which you DO need in the spring. Pool heating is anything from £90 to £115 per week so we save around £460 not going for a villa. We booked a 2 bed 4* condo in Lake Buena Vista. Had 2 bathrooms, full kicthen, jacuzzi, lounge diner, queen bed, balcony with lake views, balcony with downtown disney views etc etc. Was fab. Communal pool and TBH in 4 weeks we used the pool 5 maybe 6 times because we were out the whole time. We could see Epcot fireworks from our condo. It was amazing!!
We ditched our car after the first week because we had a free driver with our condo. He took us to any of the Orlando Parks not just Disney. We called him by mobile when we wanted picking up at the end of the day. It was free and fab. He never let us down. We also used him for a few shopping trip etc.
Car hire we booked online. I found voucher codes with Alamo. We had a budget car because apart from the suitcase issue on the trip from the airport we didnt want a tank! It was snug enroute to our condo but even that was only a 30 minute 1 off journey. We took our car in after the first week and got a refund because the shuttle driver was so flexible and FREE.
Disney Tickets and Orlando flex cards we booked through Virgin. Not usually the cheapest but due to OHs line of work we went through their corporate section and had a special discount which made it the cheapest price we could find.
Kennedy Tickets we got free after Last minute dot com cocked up debiting my CC too many times with the flights! It was how they compensated us after a HUGE row and eventual refund.
Would like to just say that we have been pricing things up again to go back next easter and are shocked at how it all seems to have gone up. Our accomodation was under £30per night last year. The next condo down at the same place is costing around £80pn now!! which is a shame because we would go back as it was 5 minutes from Disney. We even walked it one afternoon! Loads of restaurants on our doorstep and a Walgreens across the road.
Good luck with your planning and I hope you have an amazing time when you get there!