It may be rather late now, but change passwords on email accounts, and scan for any malware in case there is for instance any keylogger present (& change passwords again if anything is found). Typical suggestions re malware are in this post: [/questions/757994#answer-204042] If the info ie your address book is already held by someone/something there is not much you can now do. Are the emails actually being sent from your account indicating someone has control over it, or is someone merely spoofing your account. You would probably get a more relevant information on a site related to your email account, or one dealing specifically with security / malware.