Here's a marketing idea for you...
I've had my http://nationalpetdirectory.com
site up for a bit (it's on the back end of my own site.)
I've offered reciprocal links and the ability for others to post on this site. It's been working well.
I have an average of 150 visits a day on the nationalpetdirectory.com site.
Thus, people are being seen.
Feel free to put your own free 'directory' up to raise your stats on google and other search engines & submit to as many free directories as possible.
'Free' is the key, unless the site has obvious pull and is listed high up on the search engines anyway.