Hello susiad2001, first of all, you would need to check for the eligibility of a visa, you can find the required info here:
https://www.evisa.gov.bh/VISA/VisaInput.jsp

Some of the travel agencies available in Bahrain are listed below:
Al Gosaibi Travel
Tel: +973 1721 2333 Email: sale@algosaibitravel.com
Fax: +973 1721 5501 Web: :: ALGOSAIBI TRAVEL ::
Al Muhanna Travel
Tel: +973 1724 6665 Email: almuhana@batelco.com.bh
Fax: +973 1723 2772 Web: almuhannatravel.com
Galaxy Travel & Tourism
Tel: +973 1771 3003 Email: galaxy3@batelco.com.bh
Fax: +973 1771 3335 Web: www.galaxybahrain.com
House Of Travel
Tel: +973 1721 7070 / 1722 5335 Email: info@hot.bh
Fax: +973 1721 6216 / 1721 1329 Web: www.hot.bh