If Apple is trying to sell its Watch to the public well before its official debut, Google is working on highlighting sets of straps available for the various Android Wear devices you can choose from, including but not limited to E3 Supply Co., Worn & Wound and Clockwork Synergy.
E3 Supply and Clockwork Synergy will supply different bands for five separate Wear devices: Samsung Gear Live, Moto 360, LG G Watch and G Watch R and Asus ZenWatch. Clockwork offers leather bands in 15 different colors as well and owns the cheapest ones, starting at $12.95 ($22.95 full price).
Worn & Wound supports ZenWatch, G Watch R and G Watch but prices are just as high as E3 ones, around $65. You can only get the bands from these manufacturers on their respective sites listed in the source links as you will not find them anywhere on Google Play store or on tech manufacturers’ pages.