I don't know why TNA felt like it had to re-make Flair's theme song. He's used that one forever in both the WCW and WWF/WWE with no apparent copyright problems. I think TNA version sounds weak.
I didn't like Angle's theme at first, but it's grown on me.
http://en.wikipedia.org/wiki/Dale_Oliver#Music_composer_for_TNA
It doesn't show properly but its Dale_oliver#music_composer_for_TNA
This just gives an idea of where each song came from and a simple youtube search will then show that pretty much most songs in TNA right now are rip offs.
Pretty much all TNA themes are ripped off from another song. Kurt angles/christians were all complete rip offs. If not, they were just new songs based on other songs (MEM - Godfather type theme or Team 3d/Booker T/ric flair/christian/sting/sabu/raven using cheap knock offs of their old themes)
I've noticed that it's only recently that TNA has started using their own themes. The only people i've seen with completely original themes are AJ styles and LAX. Homicide, mcmg, british invasion, world elite, pope, kennedy, morgan, hernandez, suicide, abyss among a few others.
I've got to add that TNA themes have got better recently. The reason I thought they were bad to being with was because they were just butchering old themes for people or using well known songs, and messing them up, for new wrestlers.
--
As for WCW there were some decent themes, but still had a lot of cheap rip off versions. DDP, Sting (non-crow), Raven, Ric flair. Hogan's theme was originally American made, but still sounded like a bastard child of Real american.
They also had some decent original songs; Four horsemen, goldberg, nWo (including Wolfpac), Filthy animals, bret hart. Whilst some of their more memorable ones were ripped off, they still made some decent themes. People forget that TNA isn't even 6 years old but wcw was around when theme songs became common place in the 1980s. They pretty much grew up producing themes with WWE while TNA has started decades after WWE which puts them at a disadvantage production wise. It will take them a while to catch up, as anything TNA do will always look like a cheaper version of WWE. This isn't TNAs fault, they are still going through their learning curve. I just think one main problem is TNA are quite lazy and just use rehashed themes for the majority of the WWE/WCW/ECW alumni instead of trying to create themes for them. If they are using a cheap version of their old theme, they will always draw comparisions with that company and people will remember them in that company. IF they gave ALL talent new themes, it would stop this. The only person who has actually had a new theme made for him is Kurt angle. It just makes me think that using a cheaper version of your old theme makes that company look very weak if they can't even get near WCW, let alone WWE, production wise.