I did two to three semesters at the Univ. of Queensland studying Pali from Warders' book under Dr. Primoz Pecenko (before his heart-breaking and untimely death). I don't share Kare's belief that it is easy ~ unless one is committed and has the time. Just like any Uni subject. If one is committed and has the time, I'd recommend studying it under a teacher.
The first semester, we studied The New Pali Course (Parts 1 and 2) by Prof. A. P. Buddhadatta Maha Nayaka Thera
- which I found excellent, really helpful and worth studying.
Available online at the Pali Collective:http://www.tipitaka.net/pali/synthesis/pali1.00b.cdv