If I send emails to local businsess, don't I need some type of opt-out language in the email to make it legitimate? if so, what is a typical opt-out message?
You should use a mail management system (like Constant Contact or MailChimp, which I prefer) and those have those kinds of things built-in. However, if you're sending one email at a time then you don't need that. Just make sure not to send 1 email at a time to more than 50 businesses because then your own mail client will self-censor you. Also, if you use those mail clients and get more than 1% unsubscribe rate, then they will warn you the first time and possibly ban you the 2nd or 3rd time. Make sure those businesses want your emails.
Use Mailchimp/Aweber to create a newsletter type thing. With Mailchimp you can get a free trial and send out 3000 emails/month.