I don't eat tamales often, but I did have some at the Rick Bayless fast food restaurant in Macy's downtown and they were delicious!!! Have tried tamales in the past and haven't liked them but these were great!
Casa de Pueblo,
1810 S Blue Island
Maxwell Market at Roosevelt and Canal on Sundays.
Taqueria El Milagro
1923 S. Blue Island
A little bit pricey, but very good:
Tamale Hut Cafe
8300 W. Cermak
Tamales los mejores de Guerrero
7024 N. Clark
Finding tamales is pretty easy in this city. The best ones are made in my kitchen, however. :-)