A.C.
[hugs]
The world just got a whole lot scarier for you and your family, I know. Because it did for us too, when my son was diagnosed at 18m with a life-threatening peanut allergy.
Talk to your daughter's allergist about the "manufactured in facilities that handle nuts" -- some kids with nut allergies can handle this, and for others its a huge no-no. Your allergist will be able to tell you if you need to stay away from these, or only the "may contain nuts" or "contains nuts" items.
I have found the FAAN website (http://www.foodallergy.org/) to be very helpful, as well as www.kidswithfoodallergies.org. The FAAN site has information that can be very helpful in educating daycare/schools about the issue if they are not already aware. And you do need to have a serious conversation about avoiding exposure -- kids your daughter's age don't know enough not to offer a dangerous or accidentally ingest it (most of them don't wash their hands without direct intervention by adults; and many will share items or pick items from someone else's plate, etc.). So, really, your daycare/preschool needs to be peanut-free.... (we are now struggling with this, since we are now needing to put our son in daycare and it's so scary...).
Make sure your daycare provider (whoever that is) and/or preschool have an "action plan" for your child (you can download it from FAAN); make sure they have watched the Epi-Pen video and have practiced with the practice pen.
I'm pretty new to this too, but I believe that this is all about vigilance and label reading, and when in doubt, avoiding the food.... We're considering getting a medical alert bracelet, as a visible, consistent reminder of the health issue, since my son is too young to speak for himself.
Through FAAN, you can find local support groups that meet in person or online, and Kidswithfoodallergies.org has an online forum, as well.
Be your child's advocate and work with the other caregivers in your child's life (try not to make it adversarial) in order to try to keep your child safe.
G-d bless you and your little one!