Hi Penni,
I really like the faceplate on your machine. According to singerco.com your machine is a Singer 99K. It was commissioned on December 3, 1937 and 30,000 were allotted at that time.
If you type in singer 99k on your search engine lots of interesting info comes up. There is a site which has a 75 page manual copy for your machine.
Here is the site for the manual...
http://parts.singerco.com/IPsvcManuals/99K.pdf
Did yours come with attachments and manual?
Hope this helps you. :P