If your talking about themes for Windows XP -- your gonna need 1 of 3 files.
A) UxTheme.dll file - Not the hardest thing to do, but it's a file you download, run, and as long as your running SP2, makes it where you can change your desktop themes ... and it's FREE
B) StyleXP - A free trial program that runs in the processes, can be found at tgtsoft.com's webpage.
C) WindowBlinds - Free, but limited - the pay version has everything. Problem is, you can only use WindowBlinds themes, which are found @ WinCustomize.org. Some of the best themes available are on WB though.
Anyhow ... of the 3 above, I chose to install the UxTheme.dll file. I was a little hesitant about it, since it is a file installed to your Registry .. and can screw some stuff up if not done right. It was without a doubt the least constrictive.
Hope this helps
EDIT: Nevermind - just ignore me ... I saw the words "Taskbar Styles" ... and thought you meant the taskbar on your desktop, hence the assumption you were referring to XP Themes. - sorry
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