I've heard similar things as to what that attorney told you, both from students and attorneys. But as Nathanielmark stated, there are still attorneys who didn't attend 1st or 2nd-tier schools who are doing fine! Even the attorneys who have expressed their frustration that firms seem to favor those students who either attend high-ranking schools or who rank high in their class and have advised me to go to the best school I can are doing well.
I do think it's a bit risky, though, to go to a lower-tier school, especially in this job economy because students from higher-tier schools probably have more of an advantage now than ever.
However, I think it also depends on where you live. For instance, I live in an area where there aren't really that many high-ranking law schools and where not a lot of people go away to high-ranking law schools and come back to work...which means the firms around here will be hiring the graduates from these area schools, mainly.
I'd advise you to go to the best school you can get into, afford and attend (in that is it in a convenient locale) and to make the best grades you can.