Americans Support Goal of Improved Relations With Muslim World - washingtonpost.com:

There is still a broad lack of familiarity with the world's second-largest religion -- 55 percent of those polled said they are without a basic understanding of the teachings and beliefs of Islam, and most said they do not know anyone who is Muslim. While awareness has increased in recent years, underlying views have not improved.

There are so many places to get your questions answered, if you stumbled on my blog and have a question about Islam, feel free to ask. I think the issue isn't so much that people don't know anyone to ask questions, but it is just easier to have a negative opinion without doing the research.