Do I need my own domain to send email?
All marketing emails should be sent from a domain you own, not from a personal account at a provider domain, like @gmail, @hotmail, @yahoo, etc.
Currently, Gmail, Yahoo and AOL all issue a block whenever bulk email is sent from their domain. This is because the most important factor in email deliverability is domain reputation, and when you send mail from a Gmail account, you're actually using Gmail's reputation, not your own.
Even if your provider does not currently block email, it is very likely that all email providers will do so in the near future.
The best way forward is to create an email address at a domain that you own, so you can start building up your own domain reputation!