The following web sites are predominantly run by the US government and may be the best way to find very specific statistics on some of your topics.
Think about the "ABCs" of research as you locate secondary sources to use in your paper...
Authority: Who is the author? Is this person qualified to write about the topic? While your author does not necessarily have to be an expert, he should have some experience or exposure to the topic he is writing about.
Accuracy: Is the information believable? Can you find similar information from other sources? If the information seems farfetched and is not presented in other sources on the topic, it may not be true.
Bias: Does the author present different perspectives, or is it one-sided? Is the information from an organization that might harbor political, religious, or other biases? Your argument should show not only your perspective, but evidence to disprove the opposite side of the argument.
Currency: When was the information written? Consider the date that your source was published - have there been major advances or recent key events since it was written? Your sources should contain the most current facts as possible. Remember that books can take years to publish, journal articles could take months, and newspaper articles are published almost immediately.
By considering these questions during the research process, you should be able to find reliable and accurate sources. Remember that many of the articles found through the library's databases have been peer-reviewed, which means they have already been evaluated for accuracy by experts in that field of study.