Going to Apple's Made4Mac, I found several options for you.
ADVC110 by Canopus Co., Ltd.
Datavideo DAC-100 Analog to Digital Video Converter by Datavideo Corporation
DFG/1394-1 Analog to FireWire Video Converter by The Imaging Source
Pinnacle Movie Box DV by Pinnacle Systems Inc.
Pinnacle Studio MovieBox DV by Pinnacle Systems Inc.
Synchrotech DAC-100 FireWire Digital/Analog Video Capture-Converter by Synchrotech, Inc.
USB Instant DVD for Mac by ADS Technologies
AME USB Video Grabber with Stereo Audio - S-912 by AME Optimedia Technology Co., Ltd.
And I did not go through the entire list.