Hey, a great blog for knowing what agents are out there and what they want is Casey McCormick's blog...
caseylmccormick.blogspot.com
She spotlights an agent every week and gives detailed information about what they are looking for, what interests them, submission details, links to interviews, etc. She has over 100 agents--but not all rep PBs.
On the left side of the blog you can specifically search for agents that represent PBs.