There's a follow up question to this:
I have a list about 2000 contacts and I don't know if I should email people. I already used mailchimp. But I don't think it's the right way to do it.
Should I email people personally and tell them about the product?
To answer this question on its most basic level - Yes, it's OK to market your new startup via email ... and you should!
However, since you're asking this question ... I feel like there's more to it ... like, you're really asking something else. So, let me try and answer what I think you're really asking.
Firstly, you need to have permission to email those 2,000 people. Did they opt-in to receive emails from you? Where did you get their email addresses from? Do you know them personally? There is a lot of gray area when it comes to sending emails to people who did not opt-in. Some are illegal - like scraping or harvesting email addresses.
So, just be careful and make sure you're following the laws. If in doubt ... I'd say, start over ... and/or at least consult a lawyer that's familiar with the topic.
Secondly, let's assume you have permission to email these 2,000 contacts. My next question would be ... would they care about your startup? If you build a list about fitness, but your startup is about dog training ... emailing your fitness list probably wouldn't be too effective.
So, make sure that your list's interests match those of your startup.
As for emailing people personally. I wouldn't email all 2,000 people personally, because that'll take forever and I'm sure it wouldn't be worth the time. However, picking the top 50 to 100 people you think will convert ... may be worth emailing personally.
In conclusion - yes, email is a great way to market your startup if your list is legal and they want to hear about it!