Could someone please teach me how to do a vignette or point me to instructions that have already been posted? Thanks!

There are several ways to do this..one way I use all the time in elements 5.0 is to go filter>correct camera distortion>vignette.
Graffi also had a set of actions for this he is giving away, link below, scroll way down the page to find them
http://www.graficalicus.com/wp/

Another way is to make a new layer, use the oval marquee tool and set the feather option to about 35. Make the selection where you want the vignette to be and the shape you want. You may need to move it slightly to get it in the right place. Then do ctrl I to invert you selection. Edit> fill and choose a color you want the vignette to be, click OK, click OK and viola, you have created a vignette.

Here is a variant to the former method by Kim (for a dark vignette).
The elliptical markee tool is very handy, but you can also make a free selection with the lasso tool. There again, you use the feather function in the select menu, but it may be more (150 for a large file). Then you have to invert the selection to select the outer part: Shift Ctrl I, or Selection/inverse.
Now you copy this external selection to a new layer (Ctrl J), and set the blend mode to multiply, and reduce opacity to taste. This makes your main subject stand out in a darker surrounding.

Thank you for your help. I tried the first method and it worked well.

Next I tried you method, MichelB. Everything worked perfectly until I tried to set the blend mode to multiply. Nothing changed. Any idea what I'm missing?

(Sometimes something I've done before does not respond. I don't know if I changed the way of doing it or why it doesn't respond. Several examples--cropping and unable to change the crop ratio, lighting effect not affecting the picture at all. Any ideas what's wrong?)

before:

vignetteafter.jpg (116.79 KiB) Viewed 1337 times

after:

vignettebefore.jpg (119.29 KiB) Viewed 1336 times

(sorry, the files names are inverted...)
layers palette

vignettepal.jpg (21.74 KiB) Viewed 1333 times

The selection is made in the background copy, inverted and pasted on a new layer, which should be in multiply mode. This makes the background darker.

Oh, that clarifies things a bit. Thank you.