Hyper parameter search is included in the most recent version of GraphLab Create. The function is located at <a href="http://graphlab.com/products/create/docs/graphlab.toolkits.modelparametersearch.html">graphlab.toolkits.modelparametersearch</a>.
By default it uses grid search. If you specify a value for maxnummodels, it will uses random search.
Hope that helps. Let me know if you have any other questions.