Article on 2013 International prospects
Kiley McDaniel of sbb.scout.com has a primer on the international signing period, which begins July 2nd every year. That's when 16-year-olds from countries such as the Dominican Republic and Venezuela can be signed by Major League teams.
To that end, Houston currently has the hammer in terms of bonus pool money and their max possible pool money could get over $7 million. Rumors are flying about Houston given this advantage, since they can essentially pick whomever they want to sign and every scout knows this.