Once in Spain, need to go to a local goverment office to obtain the student residency card. Charged a 25,000 pta fee. Also, for cooking at home, the fresh markets are the best and are cheap, plus each neighborhood has its own.
Fresh produce is wonderful.
Note for vegetarians - it is difficult in restarants, easy if you cook for yourself. Some pickpocketing happens on the subway - just watch your wallet and bags. Professors and contacts may be short with you - expect to work independently, with limited guidance. Would be willing to act as a contact for other Cornell researchers. Buy a cell.