hdparm is a good place to start.
sudo hdparm -Tt /dev/sda /dev/sda: Timing cached reads: 12540 MB in 2.00 seconds = 6277.67 MB/sec Timing buffered disk reads: 234 MB in 3.00 seconds = 77.98 MB/sec
sudo hdparm -v /dev/sda will give information as well.
dd will give you information on write speed. If the drive doesn't have a file system use of=/dev/sda. Otherwise, mount it on /tmp and write then delete the test output file.
sudo dd if=/dev/sdb1 of=/media/USBHDD1/output bs=80 k count=10k; rm -f /media/USBHDD1/output 10240+0 records in 10240+0 records out 83886080 bytes (84 MB) copied, 1.08009 s, 77.7 MB/s