Lauch the WYSIWYG Editor by editing a Page. Place your cursor at the location you wish to jump to. Click on the "Anchor" in the WYSIWYG Editor Menu and an anchor marker will be placed at the location. Give it a name. Now you can create a link anywhere else in liveSite and select the anchor by name to link it to the location.
Note: Be sure not to put a space (character) in the anchor name or the link will not work correctly.