There are plenty of local comoanies that run day trips, most of them pick up from The Oasis Arch or The Square at Los Alcazares the main one being www.coachtripsonline.com/
Some of the best trips are Guadalest, Caravacca, Cartagena and the shopping centres in Murcia or Water Park
Details of the local buses you can get form the local newspapers online try www.rtn.com or www.theleader.info plus Anglo Info