A mortgage is a loan secured by real estate.
You can figure a monthly mortgage payment (i.e., do amortization calculations) at Bankrate.com.
For mortgage rates, see "Interest Rates."
For search and retrieve copies of mortgage documents, see "Real Estate."
Mortgage Brokers: You can look up mortgage broker registrations in most states using the NMLS Consumer Access database. Many states have individual databases, and you can call the relevant licensing agencies if a database is not available, or if you have questions. Mortgage Brokerage firms may also be registered with the relevant Secretary of State.