Roo is available here and on Rubyforge. You can install the official release with 'gem install roo' or refer to the installation instructions below for the latest development gem.
# Run the following if you haven't done so before:
gem sources -a http://gems.github.com/
# Install the gem:
sudo gem install hmcgowan-roo
require 'rubygems'
require 'roo'
s = Openoffice.new("myspreadsheet.ods") # creates an Openoffice Spreadsheet instance
s = Excel.new("myspreadsheet.xls") # creates an Excel Spreadsheet instance
s = GoogleDoc.new("myspreadsheetkey_at_google") # creates an Google Spreadsheet instance
s = Excelx.new("myspreadsheet.xlsx") # creates an Excel Spreadsheet instance for Excel .xlsx files
s.default_sheet = s.sheets.first # first sheet in the spreadsheet file will be used
# s.sheet is an array which holds the names of the sheets within
# a spreadsheet.
# you can also write
# s.default_sheet = s.sheets[3] or
# s.default_sheet = 'Sheet 3'
s.cell(1,1) # returns the content of the first row/first cell in the sheet
s.cell('A',1) # same cell
s.cell(1,'A') # same cell
s.cell(1,'A',s.sheets[0]) # same cell
# almost all methods have an optional argument 'sheet'.
# If this parameter is omitted, the default_sheet will be used.
s.info # prints infos about the spreadsheet file
s.first_row # the number of the first row
s.last_row # the number of the last row
s.first_column # the number of the first column
s.last_column # the number of the last column
# limited font information is available
s.font(1,1).bold?
s.font(1,1).italic?
s.font(1,1).underline?
see http://roo.rubyforge.org for a more complete tutorial