And I always wonder if a temp agency cares to see a cover letter??

Question

And I always wonder if a temp agency cares to see a cover letter??

Answer 1

not usually

Answer 2

Most do not need a cover letter in the initial interview.  But, if they have some positions open at certain places, they may require that you write up a cover letter later.  

Also, different temp agencies require different things.  Asking in advance never hurts.  

Don't forget to apply to every temp agency you can think of so you get a better chance to land a job.  Here's a place that lists them all and has a few good tips:

http://www.rateatemp.com

Good luck with your search.