Robotic Arm Interfacing

I would like to interface to a Robotic arm using an Arduino that preferably has 1kg of lifting capacity and weighs less than 500g. Should I buy one ready made or are there tutorials on making my own with a series of servos?

You need it to weigh half as much as it can lift? I don't even know of an industrial robot arm that can do that. I don't think you'll be able to purchase such an arm. You can buy robot arms that can lift 1kg - but they aren't cheap. For instance, Lynxmotion has this arm:

It can only lift 364g - and most likely weighs much more than that.

CrustCrawler has this arm:

Which can almost list 500g - but undoubtedly weighs more than that.

This one:

Can almost do 1 kg - but again, I am sure it weighs over 500g.

Rhino Robotics has this machine:

Which can do 1 kg, but as you can see, with the base it weighs almost 12 kg.

These are all fairly well engineered devices; I don't think you're going to be able to build one that does better (especially if you are asking for a tutorial). If you want to try, though, look at these examples, and do some research on the internet (and at the library - or buy some books - tons have been written about industrial robotics since the 1950s) about robot arms and industrial robots - and give it a shot. There really isn't much as far as "tutorials" are concerned (I have some files on my website about converting an Armatron to be controlled by a PC). I know that back in the 1980s, there were a few articles in Byte magazine about building your own robot arm as well.

Not sure what to tell you otherwise; obviously, to get the weight down to anything close like you want it, you're going to have to keep the actuators close to the base, and use exotic materials for everything (carbon fiber sheeting for the arm, maybe kevlar thread for the actuation "tendons", and any other hardware made out of titanium, aluminum - or some lightweight plastic or such). It won't be easy, and it won't be cheap - if it is possible at all, that is.

Good luck.