you could check this:
http://forum.slitaz.org/index.php/discussion/1856/solved-sd-card-not-recognized
and if it does not help post the output of lspci and lsmod

I went through that post and one other before I posted....No luck

root@slitaz:~# fdisk -l

Disk /dev/hda: 3253 MB, 3253469184 bytes
128 heads, 63 sectors/track, 788 cylinders
Units = cylinders of 8064 * 512 = 4128768 bytes

Device Boot Start End Blocks Id System
/dev/hda1 * 1 424 1709536+ b Win95 FAT32
/dev/hda2 425 788 1467648 83 Linux
root@slitaz:~# lspci
00:00.0 Host bridge: Intel Corporation 440BX/ZX/DX - 82443BX/ZX/DX Host bridge (AGP disabled) (rev 03)
00:02.0 CardBus bridge: Texas Instruments PCI1250 (rev 02)
00:02.1 CardBus bridge: Texas Instruments PCI1250 (rev 02)
00:03.0 VGA compatible controller: Neomagic Corporation NM2160 [MagicGraph 128XD] (rev 01)
00:07.0 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ISA (rev 01)
00:07.1 IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01)
00:07.2 USB Controller: Intel Corporation 82371AB/EB/MB PIIX4 USB (rev 01)
00:07.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 01)
01:00.0 Network controller: Broadcom Corporation BCM4306 802.11b/g Wireless LAN Controller (rev 03)
root@slitaz:~# lsmod
Module Size Used by Not tainted
sdhci_pci 6280 0
sdhci 13892 1 sdhci_pci
ricoh_mmc 3312 0
sdio_uart 9356 0
snd_cs4236 26988 1
snd_wss_lib 21004 1 snd_cs4236
snd_opl3_lib 7948 1 snd_cs4236
snd_hwdep 5988 1 snd_opl3_lib
snd_mpu401_uart 5612 1 snd_cs4236
snd_rawmidi 16920 1 snd_mpu401_uart
snd_seq_device 5544 2 snd_opl3_lib,snd_rawmidi
snd_pcm 51780 2 snd_cs4236,snd_wss_lib
snd_timer 16344 3 snd_wss_lib,snd_opl3_lib,snd_pcm
snd 43584 11 snd_cs4236,snd_wss_lib,snd_opl3_lib,snd_hwdep,snd_mpu401_uart,snd_rawmidi,snd_seq_device,snd_pcm,snd_timer
soundcore 5180 1 snd
snd_page_alloc 7256 2 snd_wss_lib,snd_pcm
mmc_block 8756 0
mmc_core 37792 3 sdhci,sdio_uart,mmc_block
b43 100312 0
mac80211 138268 1 b43
cfg80211 52872 2 b43,mac80211
led_class 3436 2 sdhci,b43
ssb 28680 1 b43
yenta_socket 20988 1
rsrc_nonstatic 9136 1 yenta_socket
pcmcia_core 27628 2 yenta_socket,rsrc_nonstatic
root@slitaz:~#

i can't see anything wrong.
try modprobe pcmcia and modprobe ds.
if it does not work could your reboot with the sd card in and post the output of dmesg or something relevant to CardBus bridge Texas Instruments PCI1250 in /var/log/messages?

Install pcmciautils.tazpkg

modprobe pcmcia

With SD reader plugged in use lspcmcia and pccardctl status , pccardctl ident, pccardctl info ,pccardctl eject ,pccardctl insert commands.
Give us whatever info you can from above commands or applicable errors from /var/log/messages

pcmcia_socket pcmcia_socket1: cs: memory probe 0xa0000000-0xa0ffffff: clean.
pcmcia 1.0: pcmcia: registering new device pcmcia1.0
pcmcia_socket pcmcia_socket0: pccard: card ejected from slot 0
wlan0: deauthenticating by local choice (reason=3)
b43-phy0 ERROR: DMA RX reset timed out
b43-phy0 ERROR: DMA TX reset timed out
b43-phy0 ERROR: DMA TX reset timed out
b43-phy0 ERROR: DMA TX reset timed out
b43-phy0 ERROR: DMA TX reset timed out
b43-phy0 ERROR: DMA TX reset timed out
ssb: Failed to switch to core 0
pcmcia_socket pcmcia_socket1: pccard: card ejected from slot 1
pcmcia_socket pcmcia_socket0: pccard: CardBus card inserted into slot 0
pci 0000:01:00.0: reg 10 32bit mmio: [0x000000-0x001fff]
pci 0000:01:00.0: supports D1 D2
pci 0000:01:00.0: PME# supported from D0 D1 D2 D3hot D3cold
pci 0000:01:00.0: PME# disabled
b43-pci-bridge 0000:01:00.0: enabling device (0000 -> 0002)
b43-pci-bridge 0000:01:00.0: setting latency timer to 64
b43-phy1: Broadcom 4306 WLAN found (core revision 5)
phy1: Selected rate control algorithm 'minstrel'
ssb: Sonics Silicon Backplane found on PCI device 0000:01:00.0
pcmcia_socket pcmcia_socket1: pccard: PCMCIA card inserted into slot 1
pcmcia 1.0: pcmcia: registering new device pcmcia1.0

Hopefully this is what you need from dmesg.

and some more

root@slitaz:~# lspcmcia
-sh: lspcmcia: not found
root@slitaz:~# pccardctl status
Socket 0:
3.3V 32-bit PC Card
Socket 1:
3.3V 16-bit PC Card
Subdevice 0 (function 0) [unbound]
root@slitaz:~# pccardctl ident
Socket 0:
no product info available
Socket 1:
product info: " ", "Memory Card Adapter", "V1.00", ""
manfid: 0x4e01, 0x0200
function: 4 (fixed disk)
root@slitaz:~# pccardctl info
PRODID_1=""
PRODID_2=""
PRODID_3=""
PRODID_4=""
MANFID=0000,0000
FUNCID=255
PRODID_1=" "
PRODID_2="Memory Card Adapter"
PRODID_3="V1.00"
PRODID_4=""
MANFID=4e01,0200
FUNCID=4
root@slitaz:~# pccardctl eject
root@slitaz:~# pccardctl insert
root@slitaz:~#

A google search of manfid: 0x4e01, 0x0200 indicates it's a lexar or conceptronic card reader which requires the ide-cs driver.

root@slitaz: modprobe ide-cs

Look at dmesg after you modprobe, it may indicate the device name.
Stick a card into the reader with files.
Try fdisk -l as root to see device name.
You have to mount the device in terminal just as you would a partition.

root@slitaz: mount /dev/device.name  /mount.folder/

modprobe ide-cs worked
I placed it in the rcS.conf file under LOAD_MODULES
The only problem I had is sometimes when removing and reinserting the card it could not find it, it always happened when inserting a different card.
So I wrote a little .sh script that would eject and insert pccardctl then modprobe ide-cs, I also had it restart my wireless card as it would become disconnected with the eject command, I could not figure out how to get it to only eject one socket.

pccardctl eject
pccardctl insert
modprobe ide-cs
/etc/init.d/network.sh

mojo and ernia thanks for all your help.
I have only been playing with linux for a month (only with Slitaz) so your info has helped ease the pain. I am a mechanic by trade so I know what's like have customers and other mechanics probe you for info.

Anyone who is successful in a trade that involves troubleshooting and repair of electro mechanical devices will love linux. The reason being that you find it rewarding to figure out how things work,what's wrong, and how to fix it.
In addition you have realistic expectations, and don't give up easily.

See if

root@slitaz: pccardctl eject 1

will work so the built in wireless in socket 0 is not ejected.

Yes mojo that worked.
I tried it before but I was not root, the strange thing was it didn't show me any errors so I thought it wasnt working. Also it didn't give me the option when entering pccardctl -v.
I'll change my .sh script.
Thanks again