“I am starting a new internet based business selling daily horse racing tip sheets, similar to the ones you can purchase at a racetrack on race day. I wanted to verify that this is legal before going live with the website.”
This is a very complicated question, as all states have very strict – and varying – laws regulating gambling activities online, and many also regulate services which foster or facilitate gambling online. You should consult with an attorney specializing in gambling regulation in your state.
In addition, if you plan to send email to your customers, you will probably find that your email is blocked by many spam filters, due to the nature of the content. You will want to make sure that any email list you build is built with confirmed opt-in, and you will probably want to use an email accreditation service such as SuretyMail.