Thought this might be useful:
NOTE: if you are interested in any of the books on any of these lists, first do a search on the Mises Wiki for it. The most popular titles are there, and the entries include all relevant links, including the Mises.org "resources page" which usually includes free downloads of the full text in various forms (PDF, eBook, etc).
If you cannot find the book in the Mises Wiki, it doesn't mean it isn't available for free, it just means a wiki entry hasn't been created for it yet. (Consider joining and making it!) In that case, go to Mises.org and perform a search for the title. Hover over the results and look for an entry whose URL begins with "mises.org/resources". That will take you to the resources page with all the downloads. If you find one that begins with "mises.org/media", it may be a free audiobook version, or a lecture on the subject.
(You can perform these searches a little easier by going to the Mises literature and Mises media pages individually and searching there, but sometimes not all of the relevant results show up, so you might start there, then use the main page search as a backup.) Happy learning!
Two books everyone must read
Learning for Liberty - all-inclusive list (adapted from the "Education for Liberty" list below)
--Learn Austrian Economics - longer list specific to econ (adds specific links to Salerno lecture)
Education for Liberty - comprehensive list compiled by C4L (includes everything from the two above)
Short reads (~100 pages or less)
One Book for Capitalism
Ten Steps to Understand Austrian Economic Theory - Gary North top 10 list (in order of difficulty)
Ron Paul's list on money - grouped by difficulty
Money and Business Cycles - collection of Austrian writings on depressions and money
Austrian Business Cycle Theory learning materials
Praxeology: reading list
Reading List for Competition, Monopoly, and Anti-Trust
Critiques of Keynes list
Voluntarist works and authors list
Free Society reading list
Top Ten Books of Liberty
Libertarian political philosophy reading list
Books on Anarcho Capitalism and Minarchism
Ron Paul's foreign policy reading list for Rudy Giuliani
Marxism - A materials list
Leftist Reading List
Philosophy Reading List
Intro to philosophy syllabus
Best Books on United States History
Top 12 History and Proto-Libertarian Works for Individualists
Five revisionist books on war
History Reading List
IMHo one should mention always "Men Economy and State", this probably is the most complete aggregation of a lot of prior authors.
I personally think that Rothbard has driven it the maximal conclusion.