You can send a free online greeting cards form any of the following sites.
http://www.clubgreetings.com/ have many categories of various ecards.
http://www.bharathgreetings.com/ help you to send many ecards absolutely free.

http://www.archiesonline.com/ and http://egreetings.indiatimes.com/egreet/index.jsp help you send free greeting card to your loved one.
Send free online electronic interactive greetings e-cards, holidays, occasions, birthday, anniversary, flower e cards from http://www.yourgreeting.com
Send funny Cards, Free Greeting Cards, Romantic Cards, Birthday greetings, Love Letters and more get from http://www.2000greetings.com
Send free greeting cards, Birthday cards, Friendship cards from http://www.greetingsnecards.com/
Largest collection of free greeting cards and animated e-cards and free holiday ecards are available in http://www.regards.com
Send free greeting cards, birthday greeting cards and free holiday greeting cards from http://www.freewebcards.com/