A fun and fascinating resource for anyone interested in artificial languages is Mark Rosenfelder's Language Construction Kit [1]. And if you want to get extremely into it, I highly recommend Paine's Describing Morphosyntax for a detailed tour of diverse grammatical systems from across the world [2].

[1] http://www.zompist.com/kit.html

[2] http://www.amazon.com/Describing-Morphosyntax-Guide-Field-Li...