EMI/EMC probe for spectrum analyzer

We are having some EMI/EMC problems and I want to rent a spectrum
analyzer  to see if changes that I am making are helping or not.  I
want to be able to sniff around the board and see the problem areas.

What type of antenna or probe should I use for this?  Will I be able
to rent this?

Any other things that I should be considering?

Thanks.

-Mike.