Legal academia is ultra-competitive (way more so than biglaw). There are sites with great breakdown's by school. The most common path at the moment is to go to a fancy school and do a bunch of writing while you are there, then do a fancy clerkship and do a bunch of writing in your spare time, then do a fancy fellowship for a year or two and do a whole lot of writing (publish 2+ law review articles and write, but don't publish a 3rd for your job talk paper), then you go to the AAALS meat market in DC and hope to get picked up by a school somewhere.
Do note that when you look at the statistics there's a big sample bias in that students inclined toward legal academia tend to be nerds who tend to get accepted to fancy schools and especially tend to like New Haven (i.e., Y) for incomprehensible reasons.
I'm told that even so, legal academia is especially snobbish with respect to your school's brand name. I have known some professors who went to UVA and similarly ranked schools and did really well. Off hand I can't think of any young, well known professors who went to schools outside the T14.
Note, this is mostly for academia in T1 schools, though I'm told that the market is quite tough at all levels, though as a general rule as you go down in the rankings practical experience starts to matter and school prestige and written work becomes less important. At the T14 level you don't have to have practiced, passed a bar or done anything useful with your life as long as you've got a shiny diploma with lots of Latin and have written a bunch of papers that other similarly situated academics thought were cool.
I do think being a legal academic would be an awesome job and have seriously considered that as a career path myself (and have not completely given up on the notion).