.gif transparency does not work on some browsers and/or OS's. IF saving in .gif does not work for you, save in, .png.
I would say it is more the other way around in my experience.
What you do is as follows:
->Open the image in PS
->Double click on the text that says background in the window that has the heading "text" "paths" and the other one just slipped my mind, sorry. (in the below right corner)
->A new window will appear...just click "oK"
->Then take the magic wand and click on the white background
->Then click "Del" on the numeric keypad
->then hit ''Ctrl'' and "D" at the same time...now the white is gone or other color of the background for that matter.
->Hit ''Ctrl'' and ''shift'' and ''S'' at the same time to save the image
When you see small left overs, pixels or whatever then click on them with your magic wand and repeat the process...sometimes you have to be patient to get the specific part you want to remove because it can be so small sometimes.
It could happen you have an image that would not display the word "background'' in the window but the word ''index'' then i suggest to save the picture before hand in another format to make the process work.
Png in some cases would not result in a transparent image but i believe all modern browsers can render it nicely some of the older ones would not give the transparency effect.
My suggestion would be to save in compuserve.gif...that's an option you have in the drop menu of PS when saving the image.
Png would also in some editors not display transparency but when previewing in the browser it works nicely so don't worry about that.
Png would also give you a smaller filesize in some cases.
When saved in the compuserve.gif format i would suggest using this link to reduce the file size by converting it to Png.
http://www.r1ch.net/stuff/gif2png/webinterface/
I hope this is the answer you can work with.
Good luck