I'm a bit new here to this game, but so far I've figured everything out easily without any help...until now. The operative stops giving me skills after a while, I got through operative and soldier, and now I can move on to karate, but for some reason he doesn't sell that skill. Do I need to buy this skill off the marketplace or are there other vendors that I haven't seen yet?

From level 15 you can only buy a few abilities at vendors. The other abilities can be purchased from the Marketplace, if other players put them up there for sale. You can also get the Coder abilities and a Code analyzer to code your own abilities. Or ask other players to code them for you.

There's a Martial Arts vendor near the subway at Stamos South Central, but he doesn't sell all abilities.

Buying abilities from vendors is also a lot more expensive then coding them yourself.

You have to type /radio addfave and then the song address. So, for example, if you wanted to add RMC to your favorites list, you'd type:

 

/radio addfave http://www.radiomegacity.com/listen.asx

I always add stations through my mpfavorites.txt
It's located default: C:\Program Files\Monolith Productions\The Matrix Online\mpfavorites.txt

You can edit the file if you have it, or make a brand new one by naming a file exactly like that.

With this, I can seperate different stations. For instance, my list looks a bit like this:


mpfavorites.txt:
----
MXO radio stations:

Name 1|url
Name 2|url
----

Dance radio stations:

Name 1|url
Name 2|url

----

MP3 lists
Name 1|path
Name 2|path
----

If you don't have an url in the first line of the text file your radio will not immediatly start playing the moment you open it in game.
Much easier to navigate I think.