I tend to use automatic page numbers in Quark, mainly because if you need to add or a delete a page from a layout, Quark will automatically renumber the pages for you. To use the automatic page numbering feature, you need to go into the master pages double clicking on the master page item below (where it says A-Master A).
The master pages in Quark can basically be used as a templete to create any items that you want to appear on each page of the publication. I tend to use them for headers and footers but you can also add columns, text boxes and other elements depending on what you need. You can also create different sets of master pages for different sections of your publication.
To add the automatic page number to the publication, simply create a text box and press the apple key and 3 where you want the page number to be placed. If you have done it correctly you should see and icon that looks like this <#> (see below). This acts as a place holder and you will notice when you create pages, Quark will automatically number them throughout the publication, starting from the number you specify.
To specify which page number you want the publication to start on double click on the page you want the numbering to start on, then choose page, section from the menu and enter the number you want to start on and the format, ie if you want the numbering to be numerical, alphbetical or roman numerals.