Before you buy a new/used laptop, netbook, notebook my suggestion is to answer few most important questions below. I got that from this thread . It contain all “Guide to buy a laptop” . Once you get all the answer you can narrow down the choice and choose the best suit your own need.

General Questions

1) What is your budget?

2) What size notebook would you prefer?

a. Netbook; 10” screen or less
b. Ultraportable; 11″ – 12” screen
c. Thin and Light; 13″ – 14″ screen
d. Mainstream; 15″ – 16″ screen
e. Desktop Replacement; 17″+ screen

3) Where will you buying this notebook? You can select the flag of your country as an indicator.

4) Are there any brands that you prefer or any you really don’t like?

a. Like:
b. Dislike:

5) Would you consider laptops that are refurbished/redistrubited?

6) What are the primary tasks will you be performing with this notebook?

7) Will you be taking the notebook with you to different places, leaving it on your desk or both?

Will you be playing games on it; if so, which games or types of games?

9) How many hours of battery life do you need?

10) Would you prefer to see the notebooks you’re considering before purchasing it or buying a notebook on-line without seeing it is OK?

11) What OS do you prefer? Windows (XP or Vista), Mac OS, Linux, etc.

Screen Specifics

12) From the choices below, what screen resolutions would you prefer?

a. WXGA – 1280×800 or occasionally 1280×768; For people who like big text and icons that are easy to read. Less stuff fits on the screen, which translates into more scrolling.
b. WXGA+ – 1440×900; A modest bump over WXGA. Text and icons are a bit smaller. A little more stuff fits on the screen.
c. WSXGA+ – 1680×1050; The middle ground. Again, text and icons are smaller than WXGA+, and more stuff fits onto the screen. Good for having applications open side by side, like a web browser while playing a video.
d. WUXGA – 1920×1200; Very small text and icons, that can be hard to read. Lots of stuff fits on the screen, which means less scrolling. Good for applications that require a high level of detail like CAD or Photo Editing.

13) Do you want a glossy/reflective screen or a matte/non-glossy screen?

Build Quality and Design

14) Are the notebook’s looks and stylishness important to you?

15) When are you buying this laptop and how long do you want this laptop to last?

Notebook Components

16) How much hard drive space do you need; 80GB to 500GB? Do you want a SSD drive?

17) Do you need an optical drive? If yes, a CDRW/DVD-ROM, DVD Burner or Blu-Ray drive?

Few additional informations

Refurbished:
Laptops that may or may not have been powered on.
Laptops that may or may not have the security seal of the box broken.
Laptops that may or may not have been used.
Laptops that may or may not have minimal cosmetic “scratches”.

Redistributed:
Laptops that where ordered and never delivered.
Laptops that where place on order but never shipped.
Laptops that where ordered but then canceled and never shipped.
Laptop is new and sealed in box.
Laptop has never been turned on.
Security seal is not broken.
Laptop is in mint condition.

Scratch & Dent:
Laptop has been turned on.
Laptop has been used before.
Security seal is broken.
Laptop may have noticeable cosmetic dents.
Laptop was fully restored to manufacturing state.

My suggestion is watch live laptop review on youtube or on cnet so you can see the problem and the advantages of certain laptop.