Radio Ads: How do I try out?

How do you go about finding about auditions for voices needed in radio promotions (both locally and nationally)? And, do you need an agent? Any SDopers done this, at least locally? - Jinx

An agent helps.

Basically, find out if there’s a studio or two in your area that tend to do a lot of radio ads for people. Do the same for ad agencies. Then either give them a tape, or maybe just express interest. I know that both the ad agency we used and the studio we used had talent pools to draw from; people they knew they could call on that might sound good for a particular spot, or who they knew they could get to come audition.