You need to go to the buyer’s shows. They are usually held in the buying seasons (Spring is held in July/August and Fall is usually Feb/March). Shows are typically in Vegas and NYC. All the manufacturers are there with displays while all the buyers for all the retailers are there looking for items to buy for their stores.
Don’t expect larger retailers to pick you up right away. They look for the bottom line more than the fashion in what they buy. Your ability to mass produce and deliver your product–as well as give volume discounts and terms discounts matter more to them. But smaller retailers will probably give you serious consideration if your product is appealing.