Danbury Police have arrested a Waterbury man for drug offenses.  Police received resident complaints about illegal sales in the City for serveral month.  An investigation led to 49-year old Aaron Thompson, who is a convicted drug dealer.  The U-S Drug Enforcement Administration and Connecticut State Police assisted in the investigation.  Police approached Thompson yesterday at a Lake Avenue business and found a stun gun in his car.  He was charged with driving with a suspended license and possession of a weapon in a motor vehicle.  Police the searched his home and found 250 grams of cocaine, 19 grams of crack cocaine, packaging and an electronic scale.  Thompson was then charged with two counts of possession of narcotics with intent to sell, three counts of possession of a controlled substance, and one count of possession of drug paraphernalia.  He is on federal probation for previous charges and also has a pending sexual assault case.