I've heard stories that it does, but I've also heard the opposite: What is the bottom line here? And if so, would somebody mind helping me? Because I have never seen a download link on the ENB website! I'm so confuzzled

Depends on the ENB I would imagine. If they really work the shaders to add more sparkles, then it will slow things down, if they are designed to optimize the shaders, then it should be better.

I'm no expert, but from what I hear, ENBs usually decrease performance depending on your setup.

Seeing as how you say you have a low end laptop, I wouldn't try it.

It also depends on your graphics card as well. The way ENB optimization (such as with ENBoost installed) works is that it uses VRAM to help workaround the 3.1GB limit for Skyrim, and how much VRAM you have depends on your graphics card.

Also, the download links are there on the ENB website, they're just hard to find. Look for the small arrows by the names of the downloads, and take care not to accidentally click on an ad disguised as a download button (which plague just about every website with download links).

The latest core ENB versions have enhancements to VRAM and RAM usage.

http://www.youtube.com/watch?v=N9WLTY9R_5Y

If you have a low end laptop, chances are very good that you do not have a very good video card (or much VRAM), and so no, it will not help your performance. It will hurt it.