The AuctionHouse is a Solana program running on Mainnet Beta and Devnet. While you may interact with it like any other Solana program by sending transactions to a Solana node, Metaplex has built some tools to make working with it much easier. We have a CLI tool that will let you manage your auction house and some reference JS code to help you build a user interface.
See CLI for how to setup and use the CLI.
MPL SDK (low level web3 focused sdk) https://www.npmjs.com/package/@metaplex-foundation/mpl-auction-house
UI Reference Implementation