OK after initially not being able to get Rails installed after following the instructions in the book I came on this forum and asked for help, I was told to install Xcode (even though in the book it presumes you can bypass this step). That worked and I was able to install Rails and SQLite, however when I get to the stage where I need to intstall the "SQLite Database Interface for Ruby' it tell me to enter this command line

$ sudo gem install sqlite3-ruby
I do but instead of it installing I get presented with this error message

Building native extensions.  This could take a while...
ERROR:  Error installing sqlite3-ruby:
	ERROR: Failed to build gem native extension.

/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/bin/ruby extconf.rb install sqlite3-ruby
checking for fdatasync() in -lrt... no
checking for sqlite3.h... yes
checking for sqlite3_open() in -lsqlite3... no
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:

Gem files will remain installed in /Library/Ruby/Gems/1.8/gems/sqlite3-ruby-1.2.2 for inspection.
Results logged to /Library/Ruby/Gems/1.8/gems/sqlite3-ruby-1.2.2/ext/sqlite3_api/gem_make.out
Dans-MacBook-Pro-2:sqlite-3.5.4 Dan$
What's going wrong? It suggest in the book that this is a tiny module and an easy installation from a single command. Yet for me it doesn't work.

Any help would be much appreciated.