• Be careful what you buy! Stick with name brands but do your research in advance before you buy. Remember, a notebook will last 3 - 5 years or even longer.
• GET AN EXTENDED WARRANTY!  I'm the type who usually doesn't buy ANY extended warranties, but because laptops still are relatively expensive to buy and to fix, it is good insurance. I know first hand because of my $1200.00 paperweight.
• AVOID REFURBISHED UNITS unless you have a GOOD warranty!  If you think you can save $$$ buying used or refurbished you MAY be taking your chances.
• Don't buy more machine than you need UNLESS you actually need a high powered laptop. Laptops will generally run a little slower than a comparable desktop because of their limited hardware size and architecture. WHAT DOES THIS MEAN? (i.e. A Pentium 4 laptop with 512 MB of RAM will run slower than a Pentium 4 DESKTOP with 512 MB of RAM).
• Laptops are generally less upgradeable than desktops. So make sure you do your homework. If you want a blazing fast laptop, buy on the high side (fastest processor and at least 512 MB of RAM, 1-2 GB of RAM is better). Even though most users do not need the fastest processor, the highest amount of RAM or the largest hard drive, you MAY want a little more machine than you need because of the fast paced change with hardware and software.
• Do you need a Tablet PC? These are units that function as laptops but the LCD screens can swivel and you can use a touch screen pen to write, draw or take notes right on the LCD screen just as if you were using a paper notebook. Check 'em out here.
• How about a Netbook? Ooohhhh these are tiny little things though! Here's a laptop, a Netbook and a DS (kids Nintendo game) in a size comparison. Small t'aint it?

ASK yourself why you need a laptop and what tasks you need to do with it?

• Light or heavy processing? You usually have different choices for CPU's (central processing unit, or "processor") when you buy a new laptop. Select a slower processor for light processing, which would entail Email, Internet and light applications. Select a faster processor for heavy or high processing needs for heavy business, developer or engineering applications, PC games or working with a lot of applications at once.
• Amount of RAM:  Windows will run faster with 512 MB or 1 GB+ of RAM for heavy applications and games or if you want to use a lot of applications at once. Newer machines are coming with 2 GB of ram as standard.
• Video memory: Most newer systems will come with Video chips with 128 or 256 MB (or more) of video RAM. Select video chips with more video ram for higher video processing for heavy applications and games. Select video chips with less video ram for basic video processing needs.
• Hard drive size: Do you need a lot of storage space for digital pictures, movies, downloads etc? Make sure you back that data up to a CD, DVD disk, external hard drive or to another networked computer or server.
• Internet Type: Dial up, high speed Ethernet with DSL or cable, Wireless ==> 802.11, 3G wireless?
• Home user or Business User? Are you attaching laptop to business network? Do you need to log into a Windows Domain or Novell Network? You need XP Professional or Vista Enterprise then (or the aging Windows 2000 Professional also).
• Do you need a Floppy drive? Internal modular drive or external parallel or USB floppy drive?
• CD burning or DVD Burning for data backup, music?
• Do you need BOTH CD AND DVD burning? Look into a combo DVD-RW/CD-RW burner then which is one unit that with do both.
• What type of printer will you be attaching to laptop? Parallel interface, USB interface or BOTH? Wireless printer? Networked printer? Scanner or all in one printer, scanner, copier, fax?
• Digital photography or video: Will you transfer data from digital camera or digital Video camera? Is that a USB or Firewire interface?
• Peripherals and interface types: 
• Express Card slots are replacing the older PCMCIA technology.
• PCMCIA slots (Type I/II/III) for credit card type devices such as: Modem Cards, Ethernet Cards, Wireless Ethernet Cards, Firewire Cards. 
• RJ-45 Ethernet port.
• RJ-11 (modem port).
• PS/2 ports for older type PS/2 type mice and keyboards.
• USB.
• Firewire.
• Serial, Parallel, External Video, S-Video, IrDA (Infared), ports for external Floppy drives, Palm Pilots, USB or parallel printers (or BOTH), camcorders, digital cameras, external CD/DVD burners, external hard drives, external monitors, televisions.
• Jacks for microphones - headphones or external speakers, game controllers etc...craziness...isn't it?