You can issue the GETDELETED query to retrieve all records deleted from the live data for the time range specified. This query accepts a datetime value as a filter, as shown in the following example:

GETDELETED FROM <table_name> WHERE <search_condition>

<search_condition> ::= 
  {
    <expression> { = | < | <= | > | >= } [ <expression> ] 
  } [ { AND | OR } ... ]

<expression> ::=
  | @ <parameter> 
  | ?
  | <literal>
  

C#

String connectionString = "AuthScheme=Basic;User=myUser;Password=myPassword;Security Token=myToken;";
using (SalesforceConnection connection = new SalesforceConnection(connectionString)) {
  SalesforceCommand cmd = new SalesforceCommand("GETDELETED FROM Account WHERE LastModifiedDate >= '2013-01-01'", connection); 
  SalesforceDataReader rdr = cmd.ExecuteReader();
  while (rdr.Read()) {
    Console.WriteLine(rdr["Id"].ToString());
  }
}

VB.NET

Dim connectionString As [String] = "AuthScheme=Basic;User=myUser;Password=myPassword;Security Token=myToken;"
Using connection As New SalesforceConnection(connectionString)
  Dim cmd As New SalesforceCommand("GETDELETED FROM Account WHERE LastModifiedDate >= '2013-01-01'", connection)
  Dim rdr As SalesforceDataReader = cmd.ExecuteReader()
  While rdr.Read()
    Console.WriteLine(rdr("Id").ToString())
  End While
End Using

Note: By putting a CACHE command in front of the query, you can update the cache to remove all values that have been deleted from the data source, as shown in the following example:

CACHE GETDELETED FROM [TableName] WHERE LastModifiedDate >= '2013-01-01' AND LastModifiedDate <= '2013-02-01'