Apple is UBER pricy, quite reliable, but well, it's The Evil Fruit, and I can't help you much more about it... I'd say the shiny is NOT worth the price tag, honestly.
Lenovo ThinkPads are just as rock solid and awesome as they were under IBM, and they're just as expensive, too. But if you can afford one with specs you'd like, grab! Well, after reading through the sticky topics in the official forums for the model... >.>
I don't know anything about the "cheap" IdeaPad line, but wouldn't risk testing it on myself before research.
HPs are very varying. Some models are pure win, some suck extremely, some seem to be great but fall apart after a year. Also, same "model name" can be very, very different internally depending on the time of production and the specs, so an ZZ1234-from-2009 and an ZZ1234-from-2010, or XX9900-with-Core2 and XX9900-with-i7 are totally different computers, where one of them may be great and other may be of the falling apart category. You need to do a lot of research, check out people's opinions and comments, and so on, but if you're lucky, and had good info, you may get some cool stuff cheaply. You'll always have to remove a ton of crapware from the preinstalled OS.
Dells are having a very bad reputation for a reason; you can get something specced to the max, but unless you'll carefully clean up system from the preinstalled trashware they'll run like a one-legged dog, and the hardware (especially power-related components) is prone to failures. Oh yeah, also, Dell's having electronics in the powersupply that does a secret handshake. Most third-party PSUs will make it power up and work "off cable", but not charge the battery.
I don't know much about Toshiba, but their mid-shelf models seem to not be too unreliable. Their lowest shelf was trash for a long time, but haven't heard a thing since a few years, so my knowledge is outdated.
Sonys are very expensive, and have very bad drivers. You need to find a just-right combination to get all the components working, and at the same time for the system to not crash and not work dead slowly.
I have very good opinion about Asus's laptops. Well, except their maxed-out gaming line, whiuch I don't know a thing about but find the concept pretty ridiculous. The mid-shelf stuff is relatively cheap for the specs, pretty reliable (well, I wouldn't put 20 pounds of stuff on the cover, but it doesn't break out as easily as some others), has a nice (if ugly) set of preloadware compared to Dell and HP (still got the blasted Norton trial to kill, but well, everyone puts that in nowadays >.<), and they Just Work.
Acer... well, they were for many years a synonym of "worst laptops that can be made"; heard they're slowly getting better, but I'd say "don't risk it".
Another thing you may check out is buying a "cadaver" from one of the Asian OEM manufacturers - see, Quanta and Compal together are really responsible for about 50% of all the "brand" laptops (including at least some parts of of Dell and HP lineups) on the market. Such a "cadaver" consists of the case, screen, battery, and mainboard. You're supposed to buy the CPU (sometimes), disk, RAM, and (again, sometimes) a wifi card into the MiniPCI slot.
Two names I can throw in because they were popular in here are Compal FL90 and FL92... but there sure are more recent models now.
Good luck!