Teresa, I am using PSE-7 but I'll bet the method is very similar in PSE-9.
Type out the text you want, straight line. Then, with your text active and highlighted, click on the icon on the top for warped text (the top arrow). You get a pop-up dialog box. For style, select Arc. Now you can play with the bend slider to change the shape of the arc (the bottom arrow). You should be able to make it fit the archway you are working with.