need anti-spyware!!!?

ive got spyware doctor but i need registration and i wanted the trial but i dont have a license code can some one help or give me another spyware program which actually removes the problem not just as to buy it plz

spybot search and destroy is free. I found it a bit complex but I had two guy friends help me. I heard there might be better versions to detect spyware but this thing is free and is used by a guy friend of mine who is a computer scientist. He said it worked well.