[CentOS] Job Script

Sun Dec 30 02:47:17 UTC 2007
Christopher E <sensory.access at gmail.com>

Hello All,

Is there a way to run a script from CentOS 5 and have it look at a
file and get it if its new then the file it got last time, if not it
does nothing, if its a new file then it wgets the file and then unzip
the file then runs a php script,  I would want this to check once a
week or if it would not make much of a different then each day is fine

if this is able to be done can someone point me in the right direction
to do such!

Sincerely,
Christopher