Here are two ways to type accents in Linux:
Character Palette (Ubuntu 10.04)
Right-click on the top bar and click on "Add to Panel," select and add "Character Palette." The small arrow on the left will give a choice of palettes which you can modify to contain any accented or other character required. Left-click a character, then hold down Control Key and type V to insert it at the cursor position.
Specify a particular unused key (e.g., the Windows key) to be the Compose Key, then you can hold down Compose Key and type e` to get è, or o" to get ö. The combinations are pretty intuitive. Where to specify the Compose Key changes from system to system. On a SuSE installation, go to Control Center > Accessibility Options > Keyboard Properties > Options > Compose Key option.
Please note that I don't use Linux and that these instructions were provided to me by Linux users. If there are mistakes or omissions, please let me know.