Advice on adding tape drive to Win98 pc

I have a PII-233 Gateway computer that I would like to use as a backup pc for a small office. It is your basic desktop pc with Win98. What would be the best type of tape drive at the best price (around $1000)? DAT, AIT, Travan? SCSI or ATAPI? Also, if I get a SCSI drive do I have to add a SCSI card to the computer if it doesn’t have one?