The Devcoin Wallet is free, open source software. You may download the Devcoin source code to compile the wallet yourself, or you may download a precompiled binary for your operating system. Devcoin GUI is the client, Devcoind is used for mining Devcoins.

Should you need any help with setting up your Devcoin wallet, please see this thread on the Devcoin official forum(Coinzen.org) where someone will gladly provide you with assistance.