How do I find out about My 100yr.old home in manchester, nh?

Pictures, history ect..

Begin with public records like the county recorder and tax assessor for deeds, judgments, and anything else in the chain of title. Also check with the building department for any record of building permits. Research the architect or builder if you can find a name. Water company records are another good source of early records in some areas. Be sure to note the names of all the owners you can find because their history will lead you to more history about the house. Ask at city hall or the county hall of records if there is such a thing as a "Sanborn Map" for the area. These are fascinating maps prepared for insurance companies in the late 19th and early 20th centuries. They show a lot of detail, but they are typically available only for urban areas. Check with your local library and, through them, your state library system for City Directories; the predecessor to the phone directory, and for reverse directories. Also look in to microfilms of any old newspapers published in the area. The search for an address could be a difficult one, but the there might be an index for names that could lead you to stories about the former owners. Again, using the names, check the census records for the area. I believe that records through 1930 have now been released to the public. These are available at national archives repositories and some are also available through the Church of Latter Day Saints for use in their genealogical studies. Good luck. It can be a fascinating pursuit.
Oh and don't forget to just G**gle the address. You might be surprised at what turns up.