There are tons of shareware/freeware available for reordering your taskbar, google "reorder windows taskbar" and you'll find tons of links...
1 decent looking freeware one:
http://www.[censored].com/nerdcave/taskbarshuffle.htm... wow... "[censored]"="free#$@#$webs" without the #$@#$, nothing like a little creative censorship...
I'm not going to try it myself so I can't vouch for it's legitimacy but this should work.