Battery change Sony Cyber shot DSC W55 I am getting a 'battery dead ' signal and cannot find where to change the AA batteries Sorry I have mislaid the manual and feel very silly.

Very likely dead.
Did you take out the battery and memory card before drying. Also it should dry for a week.
If you are lucky its just the battery thats dead. So try to borrow a battery from a friend who has the same camera.

Only with screwdriver and soldering tool :-(

It will be there in back side or open battery lid u can see reset there.

if you are so technicaly inclined you need to open the camera and replace the button battery on the board. the symptoms of your problem are due to a boot test regarding the hardware clock, since the button battery is dead it can't keep time and shuts off before it frys its self.

Your problem is mainly like above.

If you want to check the other troubleshootings please download the user manual of Sony Cyber-Shot DSC-W55

Please remove the Battery from the Camera then reinsert it after two minutes. Make sure that the Battery is fully charged. if menu options are accessible on the Camera then reset it to the original factory settings. Please follow the steps that are mentioned below to reset the Camera to the original factory settings:

(i) Please turn ON the Camera.
(ii) Then use the control button on the Camera to the select the Setup (setting) option.
(iii) Next, select the Setup1 option then "initialize".

Performing the above mentioned steps will reset the Camera to the original factory settings. If the issue persists then service will be required.

it is possible you are using the wrong batteries or instaling them wrong.
theses cameras require better batteries and you may have to pay extra for the ones that will work .
try a different brand.

You should use rechargeable AA batteries approx 1800 ~ 2400 MA.

Following Sony web link might help you.
http://servicesales.sel.sony.com/ecom/accessories/web/productSearch.do

If you open the camera up, whick I know is an intricate task, and take the screen down but don't unplug it, at the right bottom their is something that resembles a watch battery, if you can figure out how to get it off and find a replacement it will be fixed... This battery serves a a sort of memory power, even though you have batteries, this battery keeps the memory for the camera's software, so inturn without it the camera is dead in the water. this is fixable!