This is not neccessarily the best way to find a clothing factory to produce your garments.  However, this new directory is a good way to learn about clothing manufacturers.
Clothing Manufacturer Directory :

A - Apparel Manufacturer Directory

B - Apparel Manufacturer Directory

C - Apparel Manufacturers Directory

D - Apparel Manufacturers Directory

E - Apparel Manufacturer Directory

F - Apparel Manufacturer Directory

G - Apparel Manufacturer Directory

H - Apparel Manufacturer Directory

I - Apparel Manufacturer Directory

J - Apparel Manufacturer Directory

K - Apparel Manufacturers Directory

L - Apparel Manufacturer Directory

M - Apparel Manufacturers Directory

N - Apparel Manufacturers Directory

O - Apparel Manufacturer Directory

P - Apparel Manufacturer Directory

Q - Apparel Manufacturer Directory

R - Apparel Manufacturers Directory

S - Apparel Manufacturers Directory

T - Apparel Manufacturer Directory

U - Apparel Manufacturers Directory

V - Apparel Manufacturer Directory

W - Apparel Manufacturer Directory

X - Apparel Manufacturer Directory

Y - Apparel Manufacturing Directory

Z - Apparel Manufacturer Directory

You can find better list of factories at the clothing factory section on Apparel Search.