There are a few souvenir shops with handmade crafts. Several stores specialize in beach gear towels, beach toys, inflatables, etc. There are several clothing outlets. In general, Lo De Marcos has all of the staples of day-to-day living, but does not have the overdeveloped and expensive retail of traditional travel destinations.
There are also some beach vendors selling jewelry and local handicrafts, but you certainly won't be harassed by them like in established tourist destinations. If you're looking to shop, the 15 minute drive to Rincon de Guayabitos or La Peñita to the north, or Sayulita or Puerto Vallarta to the south are in order.
