http://www.dell.com/us/p/alienware-m11x-r3/pdThat's the Alienware I'm looking at.
With almost-maxed-out specs, it's a bit over $1000, but I've read hundreds of reviews and they all seem positive. It won't run Skyrim or BF3 on super-duper-awesome max settings, but it will run it lag-free on normal settings. Since I'm not a big graphics person, that won't bother me at all.
As for the mouse, I randomly happened upon a really good wireless one a few years back and I've been using it ever since. It's a Microsoft Wireless Mobile Mouse 3000. A quick Google search shows it selling from $20 - $30 online, and I can guarantee it's worth it. It doesn't have any fancy side buttons like some higher-end ones do, but it's served its purpose well.