Here you go, here is a simple example to get you started:

// Open connection to my access database.

// DataAdapter takes select statement that generates your table and connection.
OleDbDataAdapter da = new OleDbDataAdapter("select * from customers", conn);

// You can call the dataset anything, it's not important.
DataSet ds = new DataSet("MyDataSet");

// When calling fill, give it the table name you want here. What this means is select * from customers from above is fed into table called customers in the dataset. But if you want to rename it here it's ok, but for simplicity I leave it the same.
da.Fill(ds, "customers");
da.Dispose();
conn.Dispose();

// Now dataset has the disconnected data.
// You can get to the table directly like so:
DataTable customers = ds.Tables["Customers"];

// Loop thru records in customers table.
foreach (DataRow r in customers.Rows)
{
for (int i=0; i<customers.Columns.Count; i++)
{
Console.WriteLine(r.ToString());
}
}

// Or you can assign datatable to grid control, etc...
dataGrid1.DataSource = customers;

To get the data back into the database you need to update the dataset then use a OledbDataAdapter class to perform the work of syncing the changes in the DataSet to the database.

In order to do this you need to create an InsertCommand, UpdateCommand, and DeleteCommand for the OledbDataAdapter and setup parameters for the values you want to use.

For a DeleteCommand, this only really needs the primary key value, so this one is simple.

For the InsertCommand, you need to provide parameters for every single value you want to insert as well as primary key. Same goes for UpdateCommand.

Alot of newbies use the OledbCommandBuilder class to help create the appropriate OledbDataAdapter automagically, so you may want to look at this.

Here is a basic sample:

SqlConnection conn = new SqlConnection(CONNECT);
conn.Open();

// Create simple admin table with a few users. I commented this out but this demonstrates my table structure
//xsql_noerror(conn, "drop table admin");
//xsql(conn, "create table admin (username varchar(256) primary key, password varchar(256))");
//xsql(conn, "insert into admin (username,password) values ('matt', 'matt')");
//xsql(conn, "insert into admin (username,password) values ('shu', 'shu')");

// Create data adapter to fill our dataset.
SqlDataAdapter da = new SqlDataAdapter("select * from admin", conn);
DataSet ds = new DataSet("MyAdminSet");
da.Fill(ds, "admin");

// Ok, now I have my records, say I want to change password for matt.
DataTable t = ds.Tables["admin"];
t.PrimaryKey = new DataColumn [] { t.Columns["username"] };
DataRow r = t.Rows.Find(new object [] {"shu"});

// Change password.
r["password"] = "SomeNewPassword";

// Now lets update our table.
SqlCommand cmdUpdate = conn.CreateCommand();
cmdUpdate.CommandType = CommandType.Text;
";

da.UpdateCommand = cmdUpdate;
da.Update(ds, "admin");

// Now read back the rows to verify we updated it.
SqlCommand cmdTest = conn.CreateCommand();
cmdTest.CommandType = CommandType.Text;
cmdTest.CommandText = "select * from admin where username='shu'";

SqlDataReader dr = cmdTest.ExecuteReader();
dr.Read();
System.Diagnostics.Debug.WriteLine("username=" + dr[0].ToString() + " password=" + dr["password"].ToString());
dr.Dispose();
conn.Close();