Dan's suggestions about looking at Search Cursors is valuable, also look at the tools for working with tables and table views. If you need to work through a table, fitting values from fields into formulae and then updating other fields in the same or another table look up the help topics on Update and Insert Cursors as well. Those are probably the key things for what you want to do. Reading and writing geometries are a bit different though still operate well using cursors.
