Add alternate keyboards and dictionaries [webOS 3.x] 11
This tip is only for devices running webOS 3.0 and higher
Although you specify your country and language when you activate your TouchPad, you do not need to be locked in to a single keyboard layout or auto-correct dictionary. If you open up the "Regional Settings" app, there is a KEYBOARD TYPE section that is new to webOS 3.0 that allows you to add multiple keyboards to your device. If no keyboards have been added, a default one will be specified based on your local settings.
To add a new keyboard, first select the "+ Add Keyboard" button. You can choose between azerty, qwertz, or qwerty keyboard layouts, with current options of German, English, Spanish or French languages. It is not clear how to determine the region-specific language (e.g. US English vs UK English), but at least this gives you a starting point to select a language.
Once you add more than one keyboard, you will notice that the normally-wide Symbol key ( ) will now be split into two keys, with a new language key being added. Tapping on that new language key will toggle between available keyboards, while press-and-holding on the key will give you a pop-up of available languages. Aside from the layout of the letters (azerty vs qwertz vs qwerty), you may notice some different symbols are now available on the main keyboard. On some keyboard layouts, the numbers may even become secondary keys, only accessible by pressing the Shift key. In addition, the auto-correct dictionary will change with the language of the currently selected keyboard.
To delete a keyboard layout, just swipe-to-delete it off the screen and tap the "Remove Keyboard" confirmation button.
Thanks to Thomas Peter for suggesting this tip