hi W.!
have you gone to a La Leche League Intl meeting in your area yet? you really should do this as soon as you can. you will find your local chapter easily on the website by googling the organization. they really have the best, most up to date, mother-to-mother support from experienced mothers who are dealing with all the nursing issues right now. this is the place where you will find people who are and have done this, and all the reasons why it's great to do, and what you can do to support yourself and your family.
that said i would add this; nursing ONE child, as you know, is often a full time job. i would be willing to bet that yes, this will be an incredibly time consuming endeavor, but it might well be worth it. all the current studies are showing that nursing for a minimum of one year, prefereably two, has far reaching health benifits for the baby and the mother; prevention of childhood and adulthood obesity, reduciton of reproductive cancers for the mom, just to name a few. plus, most importantly, it's just much, much better food for your babies by leaps and bounds.
when your two new babies are toddlers, and you are caring for 4 whole people all by yourself, you're going to have a lot of tough nutrition choices to make; what's easy, what's cheap, what they'll actually eat, etc etc; but for now, while you can tank these babies up on the highest quality nutrition IN THE WORLD and WHICH IS FREE and WHICH YOU MAKE YOURSELF WITHOUT EVEN TRYING, i would say, you should really do this.
and here's another thought; maybe this will be hard, but what if it's really easy???? nursing my first child was very hard the first few months, but my second child latched on so easily, so effectively, so lightly, and nursed so efficiently, that i swear i didn't even know she was there half the time. i'm still nursing my almost 3 yr old boy, and my wonder-nurser 13 month old, and it's so easy! people are astonished by this, but you know what? it's totally natural, and it's been great. so why not be optimistic???
as you already know, it will also be a time that will fly by. they wil be 1 yr old before you know it. you can pump and have your husband, even the other children, help you with feedings some of the time, and still get this amazing, fabulous milk of yours into them.
W., you're already a great mom. you can do this.
good luck to you!
J.