If you mean the power window regulator, I think Toyota try to sell it as an assembly but the motor and regulator are available separately (at least that was the case with another Toyota I was working on. Look at www.rockauto.com they may have a re-manufactured or new parts cheaper than the dealer options.
The door trim panel needs to be removed to see exactly what is broken or disconnected, you have linkages to the door lock on the outside linkages to the door lock actuator, and a linkage to the interior handle to open the door and lock it from the inside. Autozone have some popular workshop manuals for free on line once you register (for free) on their website http://bit.ly/autozone_repair_info. There is a company that independent auto repair shops get their information from, this same information is available inexpensively for people that work on their own cars.. The information is year make and model specific, covering repair procedures, torque specifications, fluid capacities and specifications, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate http://bit.ly/AllData_Repair_Manuals_Online
Side sliding door gives some trouble if is that "door" you are talking about. Alldata may be most helpful for removal instructions.
Maybe you could locate the parts second hand. When trying to locate or find second hand parts, the best way post a request to many wrecking yards at the same time is to Google the words "wrecking yard parts" or "used auto parts" if you want to be a little more specific enter the manufacturer of your vehicle example "Toyota used parts". May links appear that allow you to enter the details of your vehicle and the parts you are looking for. This request is then sent out to thousands of wrecking yards through out the country and they then send you an email or give you a call with the price and availability of the part. it is the wrecking yard that pays a small commission for the service.