How do I turn off the date and time stamp on my canon powershot sx110?

The date and time (and a lot more) are stored with every picture in its EXIF metadata. Any photo viewing/editing program should be able to display this data. To print this data, please consult the documentation for whatever program you're using to print your pictures. Depending on the program and printer you may print the date on the image, in the margins, or on the back.

You can remove them in a photo editing program.

You're going to have to use a photo editing program like Photoshop Elements to remove the dates from the pics you already took. If the dates are near the edges of the pics, you may be able to just crop them out.Check your manual for instructions for turning off the feature for future pics.

http://www.willingsoftware.com/help/howto.shtml#34
The software has the time and date stamps.

1. Press the Func.set button
   
2. Use up/down arrows to select L (1600x1200 image size)
   
3. Use left/right arrows to select "clock and landscape" icon

Replace the date/time battery on the side of the camera.

you go to the menu and select one that has a little tool and select "Date/Time" and that will take you to the place where you can get the time and date!!:)

Move top selector all the way to right,

1.put in auto mode
2. Hit Function set button
3. Where it lets use choose sizefrom L, M1, M2...scroll to Post Card 1600x 1200
4. hit function set again
5. Hit Menu, now you can select time date stamp
6. took me awhile to figure it out

You can download the user manual for the camera at
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=324&modelid=17480

To set the date stamp:
1. press the power button
2. select a shooting mode.
a. set the dial mode to Auto
3. select 2M
a. press the Func/Set button
b. use the up and down arrow to select "L"
c. use the right and left arrow to select the "check"
4. press the DISP button to switch to [Date & Time] with the left and right button.
The instruction are on page 21 of the user guide.

Date stamp is only possible when you set the resolution (picture size) at "Postcard 1600x1200" option, if the date stamp is set to "Date & Time" or "Date" option