More will be added soon. If someone has missing tests or other resources to contribute please do.
I would personally recommend the Testmasters 180 and the PowerScore books. Powerscore is also coming out with the Reading Comprehension Bible and you can pre-order your copy here today.
For questions and answers to preptests, the LSAT blogspot here is a good start.
Silent Timer ? The LSAT does not allow anything but analog watches.
Hint – Do know that the best way to prep is to do as many actual tests as possible — There is no better substitute for that. Past LSATS (prep-tests) can be downloaded via torrents at sites like BT-Junkie. Get them before they are taken down.
PrepTest 7 - February 1993
PrepTest 8 - June 1993
PrepTest 9 - October 1993
PrepTest 10 - February 1994
PrepTest 11 - June 1994
PrepTest 12 - October 1994
PrepTest 13 - December 1994
PrepTest 14 - February 1995
PrepTest 15 - June 1995
PrepTest 16 - September 1995
PrepTest 17 - December 1995
PrepTest 18 - February 1996
PrepTest 19 - June 1996
PrepTest 20 - October 1996 (free online)
PrepTest 21 - December 1996
PrepTest 22 - June 1997
PrepTest 23 - October 1997
PrepTest 24 - December 1997
PrepTest 25 - June 1998
PrepTest 26 - September 1998
PrepTest 27 - December 1998
PrepTest 28 - June 1999
PrepTest 29 - October 1999
PrepTest 30 - December 1999
PrepTest 31 - June 2000
PrepTest 32 - October 2000
PrepTest 33 - December 2000
PrepTest 34 - June 2001
PrepTest 35 - October 2001
PrepTest 36 - December 2001
PrepTest 37 - June 2002
PrepTest 38 - October 2002
PrepTest 39 - December 2002
PrepTest 40 - June 2003
PrepTest 41 - October 2003
PrepTest 42 - December 2003
PrepTest 43 - June 2004
PrepTest 44 - October 2004
PrepTest 45 - December 2004
PrepTest 46 - June 2005
PrepTest 47 - October 2005
PrepTest 48 - December 2005
PrepTest 49 - June 2006
PrepTest 50 - October 2006
PrepTest 51 - December 2006
PrepTest 52 - September 2007
PrepTest 53 - December 2007
PrepTest 54 - June 2008
PrepTest 55 - October 2008