Smith endured a tough 2011, managing just six matches before succumbing to a knee injury and then returning to his native England because of family issues in June.
The ex-Crystal Palace, Derby County and Millwall man then trained with Spanish club Real Zaragoza in July but was still under the employment of Kansas City who traded him to Chivas and the acquisition has delighted the Goats.
"We talked to the player after we acquired him and yes, he really wants to come," general manager Jose Domene told MLSsoccer.com.
"He's an aggressive player who is very skillful. He brings a different type of player to what we have.
"We have a lot of really good players, a lot of possession-oriented players, [and Smith is] one guy that is very vertical and can take on people. He's got good dribbling skills and a different type of player that is one more piece to our new puzzle in 2012."