I plan to start a website as a source of income. The website will not be used to sell any good or merchandise, but will provide some notification services for it's users. Users will be charged a certain amount for the use of the website and the services it provides. It will be a 100% online business model.

I will be running this out of my home in California. I would like to be able to open a business checking account to handle the finances of this website so I have proper accounting. To be able to do this, do I need to register this website as a DBA ? Do I need to obtain a Federal EIN even though I don't expect to hire any employees ?

You can own the business as a sole proprietor, the DBA is to register the "business name" so that anyone doing business with it knows it is actually you. If you operate as such, you don't need the EIN, but you will need to use your own SSN.

Easy to file for a DBA and to apply for the EIN (IRS form SS-4).