Viagra Website — someone has stolen my e-mail address

In my spam folder I found that someone had used my gmail name to sell Viagra and other substances. It seems that they have used some device to then have the email delivered to themselves instead of to me. That means that they have stolen my gmail name and using it for their own sneaky business. I have the number of the two computers that have been doing this which are as follows: 60.230.225.40 and 60.230.202.184. Please help me to deal with these people as I feel embarrassed and angry with them for spoiling my name and using it for such a vulgar website and business. Thank you. Carmen