I know there is a hotel called W exactly a block from campus, but it can get kind of pricey.
If you want to go directly from the airport, I suggest you take the FLYAWAY shuttle from LAX to UCLA-Westwood which is $5 per trip and it comes every half an hour. (better than paying $30 something not factoring in traffic...). The shuttle stops in front of the UCLA's Kinross Building in Westwood. If you go across the street, there is a UCLA campus shuttle that takes you directly to the main campus and it's free for everyone. I don't know which department you will be visiting, but if you can check out which building it is in beforehand, you can just ask the shuttle driver or any students where is the closest stop.
UCLA has a beautiful campus and I hope you have a great time visiting...