Tickets:
http://tickets.burningman.com/ It can be in someone elses name, you will need ID & the confirmation email.
If you want a paper ticket, you'll have to find someone selling, and then make sure it's not a scam. Read
THIS before buying any tickets from a stranger. People get ripped off every year.
There is a rideshare form on the main Burning Man site you can use:
http://www.burningman.com/calendar/yearround/edit_ride_share.php?id=3960.
You can also post on the share recources section on the eplaya:
http://eplaya.burningman.com/viewforum.php?f=78
I wouldn't push the DJ part- being a DJ at Burning Man is like saying you get dusty there. Everyone is.