Torbett,
fully second Tim's answer... and there is more.. You could visit the The Partner Channel's web site "The GP List" to find a central place where most of the ISV products are listed by type, industry or service : http://thelistmobile.com/
or thepartnerchannel.com/the-list
You can also access the official Microsoft partner search site : pinpoint.microsoft.com/en-US
And there is an "unofficial" partner search site too :