Norwood firefighters are being trained on the town’s new $1.1 million ladder truck, which may be in regular service by the end of the week. “We really want to familiarize ourselves with it,” Fire Chief Anthony J. Greeley said. “The training is important.’’ He said the truck has a 110-foot aerial ladder, back-up cameras, and rescue jacks, and was constructed to better resist rollovers. The Fire Department’s existing ladder truck, which served the town well for 21 years, will be traded in, he said. Money for the ladder truck was approved at Town Meeting in November 2011, Greeley said, and the truck took more than a year to build.