I've never seen anywhere that you can just download some tables and then put them into your database.
The needs for your tables will be pretty specialized, so it is best if you design them yourself. If you are trying to get a DB with tables up and running for a project within a week then you might be in trouble.
Take the time to read the documentation at MySQL, read some tutorials at http://www.devshed.com on MySQL. Particularly, try to read an article on something call "normalization". There is a decent article here on phpbuilder about it.