Here are some things we came up with:
necklace
necktie
needle
nail polish
notepad
napkin
newspaper
nachos
noodles
nutcracker
nuts
nightgown
Check out objects & things that start with letter A to Z at ActionalPhabet.com.
Get print outs, information, coloring pages, and books related to the letter N from EnchantedLearning.com.
The history of the letter n is exactly parallel to that of m. While there are no radical changes to the form of the letter over the centuries, the main problem in identifying it is in teasing it out from other small letters.
In some early scripts a majuscule N is sometimes introduced into what looks like an inappropriate place in a row of minuscule letters to give some kind of weight or importance to the script.
To learn more and find out histories of individual letters, go to MedievalWriting.50megs.com.