Need some more information about winXP passwords

I work as IT manager but also somtimes needs to setup programs on networks which previous IT people configure administrative passwords that I need to reset as fast as possible.

What I have tried:
– Replacing SAM file (Not working)
– Change with Repair (Didn’t work)
– Brute force attack (Slow and only with admin)
– Linux boot disk (Mostly buggers up SAM)
– Winternals (Works quite well but can I get the Locksmith as a separate program?)

I am no Newby but any additional hints or other possible option will really be appreciated.

If you don’t want to post it you can email @ marius.vrstr@yahoo.com (Subject “WinXP Security” please else I might delete it as spam)

Thanks for any additional help.