Wireless lighting for Nikon D5000?

I'm a novice photographer that has mainly used natural lighting for my work (www.facebook.com/meganraephoto) and I would love to get into some studio work. I know I need a lot of practice and I'm ok with that. However, I do not live my a camera store with employees to help me make sure I'm purchasing the correct equipment for my skill level and camera.

I have a Nikon D5000 and I would like to get a few simple pieces of studio equipment that I can use at my house, or take to a neighbor's house (I have been practicing with friends and family for a while) so it must be reasonably portable.

If I get some lighting (a must have I know) what wireless sensory should I get so I do not have to connect the lighting directly to my camera?

Do you recommend Chroma key backgrounds over actual backgrounds or would you got both?

Any other suggestions any photographers may have for me?

I always suggest Alien Bees, the best bang for your buck. I would start with the best one you could afford and an umbrella that is white and doubles as a shoot through. Eventually, you would need four lights to be able to produce a classic lighting pattern, but start with one and work your way up. Chroma Key requires smooth background lighting and processing knowledge. I would hold off on that. I like the cheap wireless triggers and remotes on Ebay, they work fine, or Alien Bees has their own.