These are all available from Amazon.  Click on the box and a new window will open taking you directly to the Amazon page for the specific book. You can read reviews from others before purchasing.

Also be sure to look in the library of your local quilt guild.  They may have great books that are out of print.

 Round Robin Books for more information on Round Robins:

  Border Books for ideas for Round Robin exchanges where you are adding borders:

 Embellishment Books for ideas for Round Robin exchanges where you are adding embellishments: