The WI 2011 Proceedings can be downloaded using the following links:
-Volume 1 (22 MB): https://files.ifi.uzh.ch/WI2011/Volume1_WI2011_Proceedings.pdf
-Volume 2 (20 MB): https://files.ifi.uzh.ch/WI2011/Volume2_WI2011_Proceedings.pdf
At the registration you will receive the conference proceedings on a USB stick. You will have the option to order printed versions of the proceedings at a reasonable price using the following links:
Volume 1 (USD 26): http://www.lulu.com/content/paperback-book/proceedings-of-the-10th-international-conference-on-wirtschaftsinformatik---volume-1-of-2/9478055
Volume 2 (USD 24): http://www.lulu.com/content/paperback-book/proceedings-of-the-10th-international-conference-on-wirtschaftsinformatik---volume-2-of-2/10106853