GMT conversion help

[ictdog]

I have a need to take a column from a produced worksheet that is exported in date and time GMT and convert this into a local date and time...
example:
Date/Time
4/22/2010 2:40:59 PM
7/5/2010 11:08:19 PM
7/5/2010 11:10:09 PM

Now I want to convert this format into a date and time of local (say CST -5) column to be added...the output can be a single column or 2 (Date column and Time Column)...Any thoughts on how to make this happen?

I can do very basic formulas...and I can't find how to make this happen.
Help?

 

[Richard Schollar]

If you know what the offset from GMT is, you can just add the GMT value to the offset divided by 24

eg if you have GMT and want to adjust to GMT - 5 hours:

=A1-5/24

 

[VoG]

Try like this

=A1-"5:00"