QUESTION: I’m having trouble writing a decent fight scene. Any suggestions?
The absolute best way to get the fight scene right is to really put yourself straight into the viewpoint character's head and feel that weapon in your hand, see your enemy in front of you, see the location. What do you see, feel, touch, taste, and hear? Are you scared sh*tless or are you a cold killing machine? Etc. Etc.
If you have no experience in fighting, try to think of something you have done that can compare to that like a really aggressive game of football or basketball to get a sense of the craziness of a lot of people moving around you.
There are some really great reality documentary style shows on now, too, like DEADLIEST WARRIOR on Spike, which really shows you how warriors from particular eras fought. I imagine you can find them online or can find the series where you rent TV shows.
If you are writing monster fight scenes, the reality documentary series JURASSIC FIGHT CLUB where dinosaurs fight each other will give you ideas beyond the one monster bites the other scenario.
Also, go to your keeper shelf and pull out those novels where the writer really got it right and study how he did it.
If nothing else helps, just write the dang scene so you'll have it on the page, then go back and rewrite it until you and your critique partners are happy with the results.
This blog also has some more articles on the subject under the label "fight scenes." Read those.