Fe170 how can i exond the memory of my camera?

You can do this, by adding a memory card to the device. your particular camera model uses XD picture cards, so you'd have to buy that particular type. here is one link you can try, if you want to get them online:

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2000070068+1053107941&Tpk=xd

You can add memory to your camera by purchasing an xd memory card.
Compatible cards
xD-Picture Card (16MB – 1GB)
There are two ways to record the pictures you take with this camera.
Recording pictures to the internal memory
• Pictures are recorded to the internal memory, and when the number of storable still
pictures reaches 0, you must connect the camera to a computer to download the
pictures, and then erase the pictures from the internal memory.
Using an xD-Picture Card (optional)
• Pictures are recorded to the card when inserted in the camera. When the card is
full, you download the pictures to a computer, and then either erase the pictures
from the card or use a new card.
• Pictures are not recorded to the internal memory when a card is inserted in the
camera. Pictures in the internal memory can be copied to the card using the
[BACKUP] function.
g“BACKUP Copying pictures in the internal memory to the card” (P.25)
“The card” (P.60)
Number of storable still pictures and recording length of movies
Still pictures
Movie
• If you use a non-Olympus card or a card used for another application, such as for
a computer, the message [CARD ERROR] is displayed. To use this card with this
camera, use the [FORMAT] function to format the card.
g“MEMORY FORMAT (FORMAT) Formatting the internal memory/card” (P.24)
Additional shooting tips and information
Increasing the number of pictures that can be taken
IMAGE QUALITY Image size
Number of storable still pictures
Internal memory Card (128 MB)
SHQ 2816 × 2112 2 25
HQ 2816 × 2112 6 76
SQ1 2048 × 1536 8 108
SQ2 640 × 480 60 726
IMAGE QUALITY Image size
Remaining recording time
Internal memory Card (128 MB)
HQ 320 × 240 (15 frames/sec.) 32 sec. 6 min. 37 sec.
SQ 160 × 120 (15 frames/sec.) 2 min. 8 sec. 26 min. 28 sec.