Well I've been playing the game for a while now and i've gotten to a considerably high level but i thought when i get this high everything will get easier to kill, but no, apparently the NPCs level up with you! Which is really annoying Is there a mod to fix this? Someone i know told me there is but i wasn't sure If there is a mod for it, how do i install it and where's the download? Thanks!

Only the largest and most complete mod in all existance: http://www.gamesas.com/index.php?/topic/1108040-relz-oscuros-oblivion-overhaul-133/ . Basically it's a massive overhaul that makes the game much more static and makes the level of your enemies dependant on where they are and not what your level is. It makes the game much more challenging, especially at low levels. Might I also recommend MMM which works great with OOO- it adds loads more monsters to add the variation vanilla Oblivion was missing and the tougher enemies OOO needs in the wilder areas of Cyrodiil.

Nice! Thanks so much!

... And a lightweight alternative, should you wish it, is http://www.dreamingthepyramid.net/TNR-TIE.html.