Isn't that the first step? lol
Well, for e-mail:
1. You need an e-mail address.
2. Your server needs to be able to send out e-mail.
3. Google for an advanced PHP mailing library or use
mail().
4. ???
5. Profit.
For database:
1. You need a database.
2. You need a form.
3. When the form is submitted, start processing.
4. Connect to your database application.
5. Select the database to use.
6. Insert data into the database based on the user input.
7. ???
8. More profit.
For searching for jobs in the database:
1. Connect to database.
2. ???
3. OMG monies!
Good luck.