The National Archives has an extensive collection of company muster and payrolls among the records of the Confederate Adjutant and Inspector Generals Office. These muster rolls are not on microfilm, generally. The information from them on individuals was extracted and placed in the Compiled Service Record of for each soldier and you can get a sense of what muster rolls exist for the unit that you are interested in by looking closely at the individual cards in the man's CSR. There are also some morning reports -- which frequently do not contain names of individuals-- and also regimental returns, that do provide names. The company muster rolls are organized by State, then arm of service and then unit. Each muster roll generally provides for each person: name, rank, dates and place of enlistment, name of enlisting officer, date of last payment of each person, remarks regarding those absent, amounts paid, and signatures of men receiving pay and officer making payment. Muster rolls also include a record of events and record of inspection. The number of muster rolls for each unit vary widely. For example, there are no muster rolls for the 50th Va after Nov 1861.