Egg noodles aren't actually that common in mainland China.
La mian (拉面) means "pulled noodles" referring to the way the chefs skilfully pull and stretch the noodle dough until it breaks into strands. In my experience it never includes egg.
YouTube has many videos showing the process.
http://www.youtube.com/results?search_query=la+mian&aq=f
It is also the origin of the Japanese word "Ramen" although the two have long parted company in terms of what the dishes really are.
Sadly, totally misconstrued concepts are common in cookbooks by people who never actually visited the places they are talking about, or if they did, spent two weeks in the tourist areas.
