There's a Crown Plaza in Irvine that's very reasonably priced, between 100 and 150 per might but a quick check revealed only four rooms available, so there might be something going on in town that week... Book quickly!
For a REALLY nice stay consider the Atrium, Here's a link to their website with room views and all that other stuff,,, 149 to 300 per night. It's really scaled for the business traveller, with desks, fax, in room data ports and has a nice ambiance and excellent services as well. And it's close to the airport. He's coming into John Wayne/Orange County airport right?
www.atriumhotel.com/Don't be fooled by the picture this is a HUGE place with a 700 seat ballroom among other amenities.
Oh and just to look like a real star, call the Belldesk after you make the reservation and have bossie Milk and cookied. I've found that hotels are very eager to accomodate their business travellers, so I often call ahead and have a "snack" depending on (bossie's arrival time) preplanned. I had a boss who favored chocolate chip cookies,(and one who wanted nothing more than a scotch and water) but it could be a pastrami sandwhich if that's what YOUR boss likes, and oh the kudos when boss answers the door to find room service there with his favorite snackie!
Hope this helps!
Andrea, purveyor of snackies and other good stuff, in Charleston.