If you mean that you deleted the photos off of your SD card, you should be able to recover them. You should NOT use your SD card until you recover your photos. There are a number of computer applications that do a great job of locating photos on SD cards (even though you think they've been deleted, they are still there). PhotoRescue is a free program that works well. If you Google "photo recovery" or something of that nature you'll find a lot of others. All of them work with a basic SD card reader (connects to your computer with a USB cable. You can generally pick one up for about $10 or so.
The key is to not use the SD card. Don't put it in your camera and if you have, be sure not to turn the camera on...just remove it. Once you have the program on your computer open it, attach the card reader, insert the SD card and follow the instructions.
Did you happen to transfer any of the photos to your iPad? If so, you can move them to your computer...
http://support.apple.com/kb/ht1296
BTW, I'm moving this to the iPad Help section where it will likely get more attention.
Hope that helps!