Here, recommended to me by Shmuel Ross, is an interesting article about the immigration question. I think it's right that there's something wrong with a set of laws that remain on the books but are only enforced inconsistently and arbitrarily.
One thing I'd change in it is the line about how undocumented workers "do the work that Americans won't." As Krugman and others have been noting, they do the work that Americans won't do for that salary. And I guess with that should go the recognition that it isn't just the take home pay…it's also the working conditions.