It doesn’t get much more convenient than this. I just had to do this today and went looking for a tool. xls2mysql is a free php script that takes the data from your excel file and converts it into tables in a mysql server. It’s not perfect – it cannot detect field types and the maximum file upload size over http that your server allows will limit the size of the data set you can import, but for lots of simple tasks this is a handy script. Of course you can do this already with phpmyadmin if you export your data out to csv, but if you’re not running that and don’t see yourself getting it going, this is an alternative.