How to make formatted flash drive found?

Sat Sep 3 22:48:33 MST 2011

What do I need to do to get my system to "see" a formatted USB flash drive?

After inserting a USB flash drive, as root, 'df' shows this:
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda1              12G  2.6G  8.7G  24% /
/dev/sda6              23G 1001M   22G   5% /home
/dev/sdb1             3.8G  4.0K  3.8G   1% /media/disk

And fdisk -l shows this:
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *          63    25189919    12594928+  83  Linux
/dev/sda2        25189920    78156224    26483152+   5  Extended
/dev/sda5        25189983    31230359     3020188+  82  Linux swap / Solaris
/dev/sda6        31230423    78156224    23462901   83  Linux

Disk /dev/sdb: 4004 MB, 4004511744 bytes
116 heads, 51 sectors/track, 1322 cylinders, total 7821312 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *          32     7821311     3910640    b  W95 FAT32

But when I try to run 'unetbootin' no USB drive is found.