1.) Perhaps take a few moments to learn about how SOPA and PIPA work. Here is a good start.
2.) Print and mail letters to your state’s senators and representatives, urging them not to support this. Physical mail is harder to ignore than email. It piles up. It has to be put into those 1930's-looking satchels labelled "MAIL". You can find representatives’ addresses here and senators’ addresses here.
3.) Call your senators and representatives on the phone and urge them not to support the bills. See above links for phone numbers or click here to get a quick list of representatives based on where you live.