Withdata Software provide some ETL (Extract-Transform-Load) tools for SQLite:
TxtToSqlite Load TXT, CSV, TSV data to SQLite
XmlToSqlite Transform XML data to SQLite
JsonToSqlite Transform JSON data to SQLite
XlsToSqlite Extract data from Excel to SQLite
AccessToSqlite Extract Access data to SQLite
DB2ToSqlite Extract DB2 data to SQLite
MsSqlToSqlite Extract SQL Server data to SQLite
MysqlToSqlite Extract MySQL data to SQLite
OracleToSqlite Extract Oracle data to SQLite
PostgresToSqlite Extract SQLite data to SQLite
SqliteCopier Extract data from one SQLite database to another