Data logging to a SD card.

I want to start a data logging project. The eeprom memory is very less. So, I want to use a SD card. However SD card shields are expensive. There is no way I can afford them nor are they available in India. I have seen some SD card breakout boards. They seem to be cheap. Will such breakout boards do the job. Will they run out of the box or will I have to do some work to modify them?

And what protocol is used to read and write from and to a SD card. Also how many pins will it take.

Thanks in advance.

$8 US is expensive?
http://pjrc.com/store/sd_adaptor.html

This one requires a total of six connections--+5V, ground, and four other pins.

And what protocol is used to read and write from and to a SD card

There's a few libraries out there that support SD cards. There's one that comes pre-loaded with the IDE. Have a look on Google Code Archive - Long-term storage for Google Code Project Hosting. too; it covers communication with FAT32 and FAT16 cards.

Before I purchased a legit SD card reader shield (seeedstudios version)..

a simple voltage divider (some resistors).. and a header on a SD card adapter worked for me..