This tutorial will show you how to use the gradients from this web site with Adobe Premiere's Gradient Wipe transition to produce transition effects. The screen shots were taken from Premiere 4.2. But it will look similar in Premiere 5.
1. Drag the Gradient Wipe transition from the Transitions window into the T-Track (Premiere 5: Transition Track) of the Construction Window and place it between two video clips as shown above.
2. On the dialog that will appear, click on the Select Image button.
3. In the appearing file dialog locate and choose a TIF gradient file.
4. Now you can adjust the Softness, if you like. (But you can also do that later, too, by double clicking on the transition box and pressing the Custom button in the Transition dialog.)
5. Finally just press the OK button.
That's all. If you like, you can preview the effect now by dragging the mouse pointer over the timeline while pressing the left mouse button (Premiere 5: additionally hold down the Alt key).
Tip: If you want to reverse the transition, just click the F/R-Button on the transition box or in the transition dialog.