Looking for email marketing solution?

[Peter]

I am going to promote some cleaning services over the internet.

I am thinking of using email marketing to obtain some customers.

I have taken a look at the Mailchimp, which is a web application for email marketing .

The problem is, it does not provide an email list of potential customers for my industry and it also says that I should not purchase an email list somewhere and use it on their application.

Is there any company that offers email marketing solution which provides an email list of potential customers for different kinds of industries?

I understand that sending unsolicited email is bad (which is SPAM), but I heard from my friend that it is not always prohibited and illegal. For example, it's not illegal to send unsolicited email to public company email address, such as contact@mycompany.com.

Please do feel free to give any answers / suggestions.

Many thanks to you all.