[How to use]

$ rpmdownloader.rb 
usage: rpmdownloader.rb <package_name> [<distribution>] [<arch>]
$ rpmdownloader.rb ruby-nokogiri fc11
querying to rpmfind.net...done.
12 rpm found.
1	ruby-nokogiri-1.3.1-1.fc11.ppc.rpm
2	ruby-nokogiri-1.3.1-1.fc11.ppc.rpm
3	ruby-nokogiri-1.3.1-1.fc11.x86_64.rpm
4	ruby-nokogiri-1.3.1-1.fc11.i586.rpm
5	ruby-nokogiri-1.3.1-1.fc11.ppc64.rpm
6	ruby-nokogiri-1.3.1-1.fc11.ppc64.rpm
7	ruby-nokogiri-1.3.1-1.fc11.i586.rpm
8	ruby-nokogiri-1.3.1-1.fc11.x86_64.rpm
9	ruby-nokogiri-1.2.3-1.fc11.i586.rpm
10	ruby-nokogiri-1.2.3-1.fc11.ppc.rpm
11	ruby-nokogiri-1.2.3-1.fc11.ppc64.rpm
12	ruby-nokogiri-1.2.3-1.fc11.x86_64.rpm
Enter a number to download> 3
downloading using wget...(will take a while)
	ruby-nokogiri-1.3.1-1.fc11.x86_64.rpm downloaded
done.
$ ls
ruby-nokogiri-1.3.1-1.fc11.x86_64.rpm