I'm going to be staying there for 6 nights and plan on bringing more than enough clothes (which the fiance loves because that means shopping) but if you need do they offer machines for people? We are staying at the Coronado Springs Resort FWIW.
The resorts have coin operated laundry rooms and they also have laundry & dry cleaning services, at least at the deluxes (not sure about Coronado). Their service though is very expensive. We just do our own in the laundry room if we need it.
The laundry rooms are located next to each of the quiet pools at CSR. It costs $2 in quarters for a load of wash. The same cost for the dryer. There are machines that sell laundry soap (again coins only, I believe). I always bring my own- ziploc bags with one load of detergent in each- or you could use the Purex sheets. The laundry rooms are generally kept locked- you will need your KTTW card to enter.
I LOVE doing laundry at WDW.....cuz it means I'm trapped at the quiet pool for a couple of hours.
Also....I learned this tip on this board a long time ago and it works great. Put your laundry in one of your rolling suitcases. Easy to get to and from the laundry room! And bring your Purex detergent/softner sheets.