Did you really mean Power Point?  Publisher would be a far more suitable
program and it does have mail merging capability.

As Doug suggests, it is possible to Mail Merge from Publisher (in recent
versions, at any rate).

If you are starting from PowerPoint, I haven't done this for real, but let's
suppose you have PP2003 and your template consists of
a. a background image
b. some text boxes where (in PowerPoint) you would type the text

Then you can try:
a. in Word, create a new blank document and lay it out how you want
(correct paper size and orientation in File|Print Setup)
b. In PowerPoint, go to the master page of your template (View|Master|Slide
Master)
c. Edit|Select All
d. Edit|Copy
e. In Word, Edit Paste. The background picture should fill a good part of
the document starting from the top left of the page (not just the bit
between the margins), but you may need to grab the bottom right grab handle
of the graphic and drag is so the graphic fills the whole area.. Any text
boxes in the PowerPoint document (which is presumably where you would have
typed names and other info. in PowerPoint) become text boxes in Word. If you
had to stretch the graphic, you may need to adjust the size and position of
the text boxes.
f. In Word, enable the mail merge toolbar, connect to your data source, and
replace any text in the appropriate text boxes by the merge fields you need
from the data source. Format them as required.
g. Do the merge.