Hi Linda and congrats on getting your business to the launching stage.
I wouldn't consider a phone number as important, in fact as you are going to be drop-shipping, I would suggest NOT having a number. The last thing you want is to take a call from a customer having an issue that you in turn then need to follow-up with your supplier on, that is a very quick way to lose confidence with a customer.
Contact form, email address and I would suggest an online support option as well. Even if you're not online between certain hours, it's a very convenient way for customers to leave you a quick message and it, in fact, gives a very positive perception of switched on customer service just having that option, whether it's online or not.
So those 3 things are what I would certainly suggest going with.
The big key, make sure that you service the inquiries as a priority.