Getting out of the house is very important. Being cooped up all day with a baby or toddler will drive you mad most days so it is good to try and get out as much as possible. Most towns and villages will have local toddler groups often run by volunteers or churches. Sometimes there is a small charge for this, but it is often well worth the money.
In addition to the volunteer run groups there are also groups run by businesses or individuals for profit. These are often, music or dance based and can be really good, however they do tend to be a fair bit pricier than the volunteer led ones. Examples of national ones are Jo Jingles and Monkey Music although there will be plenty of local ones as well.
In addition to the groups there should be a local Sure Start Centre these are invaluable as they offer free services and classes to parents and have trained family support workers who can assist with any questions or problems you might have with regards to raising your children. Not only do your children learn social skills by interacting with other children, as a parent it is often the only adult conversation you are likely to get till your partner comes home from work.
It can sometimes be intimidating to go to these classes as a man as I tend to find that it is harder to make contacts. However as you become more familiar by attending regularly barriers do drop and you are quickly accepted as just another parent who has got the same issues and questions as everyone else. I try and attend at least 3 classes a week not only for my own sanity, but I have also seen my eldest daughter blossom and come into her own, with the interaction she has with other children.