K.D.
I have 6 month old twins, with no other siblings at home. I found it very helpful to join DuPage Doubles. www.dupagedoubles.com. I did this after my babies were born, but looking back I wish I would have joined while I was pregnant.
There are lots of people in the same boat as you, and they are more than willing to help out with anthing from stroller advice to coping advice. Best of all there is a used clothing/baby stuff sale 2X a year for all of the stuff you will need for just a very short time.
Accepting help is key, too.
There are plenty of people in the club that have toddlers and twins, in different orders that would be willing to give you advice.