For those interested, these are the fandom-specific legal articles I've found. If anyone comes across more legal commentary, or web-accessible versions I've missed, please add it in comments.
Rebecca Tushnet, Legal Fictions: Copyright, Fan Fiction and a New Common Law, 17 Loy. L.A. Ent. L.J. 651 (1997)
Meredith McCardle, Fandom, Fan Fiction and Fanfare: What's All the Fuss?, 9 B.U. J. Sci. & Tech. L. 443 (2003) (pdf file)
Cecilia Ogbu, I Put Up a Website About My Favorite Show and All I Got Was This Lousy Cease-and-Desist Letter: The Intersection of Fan Sites, Internet Culture, and Copyright Owners, 12 S. Cal. Interdisc. L.J. 279 (2003)
Jessica Elliott, Copyright Fair Use and Private Ordering: Are Copyright Holders and the Copyright Law Fanatical For Fansites?, 11 DePaul-LCA J Art & Ent. L. 329 (2001)
Deborah Tussey, From Fan Sites to File Sharing: Personal Use in Cyberspace, 35 Ga. L. Rev. 1129 (2001)
ETA: Krissi J. Geary-Boehm, Cyber Chaos: The Clash Between Band Fansites and Intellectual Property Holders, 30 S. Ill. L.J. 87 (2005). PDF file available.
ETA: Simone Murray, “Celebrating the Story the Way It Is”: Cultural Studies, Corporate Media, and the Contested Utility of Fandom, 18 CONTINUUM: J. OF MEDIA & CULTURAL STUDIES 7 (2004).
ETA: Note, "Recoding" and the Derivative Works Entitlement: Addressing the First Amendment Challenge, 119 Harv. L. Rev. 1488 (2006).
ETA: Sonia Katyal, Performance, Property, and the Slashing of Gender in Fan Fiction, Journal of Gender, Social Policy, and the Law (forthcoming), available at SSRN.
ETA for some classics: Justin Hughes, Recoding Intellectual Property and Overlooked Audience Interest, 77 TEXAS LAW REVIEW 923 (1999), and Rosemary Coombe, "Author/izing the Celebrity: Publicity Rights, Postmodern Politics, and Unauthorized Genders." Special issue titled "Intellectual Property and the Construction of Authorship." 10 Cardozo Arts and Entertainment Law Journal 365 - 395. Reprinted in Martha Woodmansee and Peter Jaszi, eds., The Construction of Authorship: Textual Appropriations in Law and Literature (Durham, NC: Duke University Press, 1994) 101 - 131.
ETA: Anupam Chander & Madhavi Sunder, Everyone's a Superhero: A Cultural Theory of 'Mary Sue' Fan Fiction as Fair Use, 95 Cal. L. Rev. 597 (2007) (pdf).
ETA 2/8/2007: A Winner is Who? Fair Use and the Online Distribution of Manga and Video Game Fan Translations, 9 Vanderbilt J. of Entertainment and Technology Law 223 (Fall 2006).
ETA 9/17/2007: Rebecca Tushnet, Payment in Credit: Copyright Law and Subcultural Creativity, 70 L & CONTEMP. PROBLEMS 135 (2007), and responses by Jessica Litman, Creative Reading, 70 L & CONTEMP. PROBLEMS 175 (2007), and Mark Lemley, Should a Licensing Market Require Licensing?, 70 L & CONTEMP. PROBLEMS 185 (2007).
1/11/2008 Rachael Stiegel, Harry Potter and the Laboratory Creativity: Fandom Infringement of Copyrights and a Proposed Exception for Experimental Use
1/16/2008 Sarah Trombley, Visions and Revisions: Fanvids and Fair Use, 25 Cardozo Arts & Ent. J. 647 (2008).
2/4/2008 Jacqueline Lai Chung, Drawing Idea from Expression: Creating a Legal Space for Culturally Appropriated Literary Characters, 49 Wm. and Mary L. Rev. 903 (2007).
2/26/2008 Ernest Chua, Fan Fiction and Copyright: Mutually Exclusive, Able to Coexist or Something Else?, 14 eLaw Journal 215 (2007).
3/2/2008 Andrew S. Long, Mashed Up Videos and Broken Down Copyright: Changing Copyright To Promote the First Amendment Values of Transformative Video, 60 Okla. L. Rev. 317 (2007).
4/28/2008, Edward Lee, Warming Up to User-Generated Content, U. Ill. L. Rev. (forthcoming 2008)
6/12/2008, Rebecca Tushnet, User-Generated Discontent: Transformation in Practice, 31 COLUM. J.L. & ARTS 110 (2008) (PDF).
6/27/2008, Joshua M. Daniels, "Lost in Translation”: Anime, Moral Rights, and Market Failure, 88 B.U. L. Rev. 709 (2008).
7/18/2008, Casey Fiesler, Everything I Need to Know I Learned From Fandom: How Existing Social Norms Can Help Shape the Next Generation of User-Generated Content, 10 Vanderbilt Journal of Entertainment and Technology Law 729 (2008).
8/1/2008, Christina J. Hayes, Changing the Rules of the Game: How Video Game Publishers Are Embracing User-Generated Derivative Works, 21 Harvard J. L. & Tech. (2008).