Whitney Port was spotted carrying the Barcelona Saddle Bag in tan ombré by Patricia Nash. Her bag is available for $198 in plain tan at Dillard's and you may click the image below to view or purchase.
I just got a very similar one at Goodwill for $5. These are inspired by the Mexican and South American saddle bags that have the etched leather. If you like it but don't wanna dish out $200, go on ebay or to goodwill/thrift shops and find similar ones.