It should look something like this:
After install you may need to perform a reboot to have them appear.
If that doesn't help, you may want to attempt a full uninstall and reinstall of TortoiseSVN.
Other things it could be: registry permission problem, conflict with other context menu entries, corrupted files/context menu entries, etc.
Perhaps check out these related StackOverflow.com links for some ideas on how to fix it: