Sensor locking to SD or DB on Internet


im about to build a noise locker...

iv got my Uno and thats it
do any of you know what to buy i need wireless connection between the sensores and i need 4 sensores

can i get one reciver and 4 transmitters..

and can i just get a SD shield for storage or can i use the webserver shield and make the UNO write it to a database on the web.

i hope that one out there can help me