I found a pretty decent gaming laptop for around $800 a few years back, it had an i7 that was quite competitive to the desktop i7-2600, but at the same time I found plenty of equally priced laptops that had CPUs that were quite bad.
I don't have any recommendations at the moment for specific laptops, but I will say you should check out the benchmarks of laptop CPUs and GPUs before making your purchase.
Check out the following sites.
Find a laptop you seem to like, and then look up it's Processor and GPU on both of those sites.
It's worth checking out the following, too.
Also, unless you're getting a great deal, it's a bad idea to go with last gen hardware with laptops. Laptop hardware seems to be advancing at a faster pace than desktop hardware. It's not beating desktops, but it's catching up pretty good.
Since you've got a nice $1800 budget, I would also recommend looking for a laptop with an extra hard drive bay, so you can have both an SSD (OS, Programs + Favorite games) and a HDD for storage.
You'll definitely be able to get an awesome laptop for that budget, just try not to spend it on only some flashy lights and a name.