Agree with Juliacoolo. Alienware's typical practice is to take a really good CPU, a really good GPU, put it in a notebook and then charge you several hundred more than other notebooks with the exact same CPU and GPU. Where does that extra money go to? Stuff like the smooth velvet cover that the notebook comes in, and probably the stylish box packaging too (which people won't carry their laptop around in anyway).
In fact since you said budget is tight, Alienware should be a no-go from the start as it is notorious for its pricing.
As a baseline guide for choosing laptop:
1. Pick a screen size. Bear in mind how much words will look smaller on smaller screens. You can do a simple test: For example if I have a 15" screen I wanna find out how small things look on a 10" of the SAME RESOLUTION (hence about 66.67% the size of my 15" screen) I just do a printscreen of my desktop and browser and shrink the screencap to 66.67% and then look at how much smaller things become.
2. Check the basic checklist for things you WANT or NEED
- USB 3.0? Blu-Ray? Any specific ports like eSATA or Firewire? (my laptop actually has neither)
- Numpad on keyboard?
- Glossy or matte screen? (matte screen = less reflections but lots of laptops are mainly glossy)
- How many USB ports do you need?
- Chassis material? (glossy plastic like Dell Studio XPS will be hard to clean as fingerprint smudges are very visible)
- How much hard disk space? (ignore stuff like SSDs/RAID if high speed data access is not a concern)
etc...
3. Those 2 steps should narrow down quite a lot. Next is utilisation:
- If you plan on outdoor use, or anywhere without an A/C supply, prioritise battery life above performance and if possible avoid anything larger than 15.6" screen
- If you plan on gaming, choose the most graphically demanding game you intend to install on the laptop and check its RECOMMENDED (not minimum) system requirements. Use that as the minimum criteria for CPU and GPU. Note that higher performance = shorter battery life. There are ways to stretch the battery life (for instance I undervolt my GPU while on battery through a vbios mod) but usually its difficult and requires technical know-how (or at least the know-how to search for that info)
- For future-proofing of GPU (potential to play newer games in future), check this: http://www.notebookcheck.net/Comparison-of-Laptop-Graphics-Cards.130.0.html comparing GPU can be very hard. Use benchmarks to compare, NOT the amount of VRAM (which is the common number quoted by sellers... but it's always the same numbers, either 512mb or 1024mb or recently, 1.5 gb and higher). Just as is the case with regular RAM, the amount of video memory in GPU is rarely the bottleneck, and surplus RAM will make NO DIFFERENCE
4. By now its just a matter of comparing different models that fit the criteria. Do google search for reviews. Use keywords like "overheating" to see if you get any hits on potential thermal problems.