Email notifications not working when using google mail app on my domain

I have my site – http://www.mydomain.com hosted on dreamhost and i am using contact@mydomain.com as a “from” field in woocommerce email settings. The problem is that all the mails are ending up in spam folders. The sender address in indeed the contact@mydomain.com.
I think the problem is that i am using google mail app on mydomain.com to send and receive mails. I don’t mind linking it to woocommerce to send notifications, but i am clueless as to how would i do it. I have searched the internet and found out about a plugin called configure SMTP but i am confused about the SMTP host and other settings in it.
Any suggestions how can i make my email notification working again ??

http://wordpress.org/plugins/woocommerce/