I'd be surprised if Nomar agrees to play for the Yankees. First base is already taken by Jason Giambi and I imagine that he'd have problems being forced to DH. Besides, Shortstop and Third are already occupied by Jeter and A-Rod. Garciaparra has never played any other position. Out of all the teams interested in him, I see Nomar being more comfortable in going to Houston or returning to Boston.
Actuallt, Nomar has expressed an interest in changing positions. Giambi is going to be the DH next year... there is most definitely a spot at first, if the money is right, and Nomar wants it.
Besides the Yankees, three other teams are interested in Nomar. According to Fox Sports, they are the Astros, Indians, and Dodgers. Dodger GM, Ned Coletti has reportedly asked Nomar if he'd like to switch to the outfield.
Out of the four teams, the Astros is probably the best fit. He would get more playing time at shortstop and his wife, Mia Hamm, is from Austin.